Sims 4 Studio and CAS Tools are programs that are incredibly useful not only to content creators but to any Simmer who wants to keep their CC neat and organized. They might seem overwhelming at first, but they can be extremely powerful tools for fixing those minor but irritating CAS issues that quietly drive you mad, whether that be poor categorization, disappearing accessories, or that one hair that shows up on every single townie in your game. You'll be even more shocked at the laziness of certain paywalling creators when you realize just how quick and simple the majority of these fixes are.
There's a lot of scattered information out there, but I thought it might be useful to gather the tips and tricks I use the most in one place. I've learned most of what I know through trial and error, and I'd like to make it all a bit less intimidating for others if I can. I wanted this guide to be accessible for complete beginners, so it's perhaps more detailed than necessary. Still, I'm sure I left some things out, so feel free to comment or reblog with your own additions! And if you're afraid of breaking your CC, back-ups are your best friend! Make copies beforehand so that you can revert back if needed.
You'll find all these topics covered under the cut:
Setting Up S4S & CAS Tools
Modifying CAS CC Categorization (and More) in S4S
Supplementing S4S with CAS Tools
Unmerging Packages and Running Batch Fixes
Utilizing S4S's CC Browser & Changing CAS Display Index
You can access a Google Docs version here.
1. SETTING UP S4S & CAS TOOLS
It probably goes without saying, but you'll need to download and install Sims 4 Studio and CAS Tools first if you haven't already. Ensure you're downloading the latest versions. I use the installer version of S4S because it's easier. For CAS Tools, you just unzip the files to your preferred location. I usually create a folder for it in Documents. When you want to use it, open the .exe file. As far as I know, both programs are vetted, trusted and safe. If Windows gives you a hard time, you can bypass the warning pop-up to run them anyway.
When opening these programs for the first time, they'll likely prompt you to confirm the location of your mods folder and ask you for a creator name. S4S also has to process a bunch of game data whenever it or the game updates. It can take a while, especially if you have lots of packs and a slower computer. Just be patient. When it's ready to go, you should see this screen.
Once it's installed, I recommend setting S4S as the default program for opening package files. On Windows, you can do this by right-clicking on a package file and selecting "Properties." Click "Change..." next to "Opens with," and if Sims 4 Studio doesn't show up in the list of available apps, click "Choose an app on your PC" to manually locate the .exe. Now you can double-click any package to open it in S4S, which is what we're going to do next.
2. MODIFYING CAS CC CATEGORIZATION (AND MORE) IN S4S
When you open a package file in S4S, you should see something similar to the image below. If you automatically get sent to the "Warehouse" tab instead and see a bunch of technical jargon and numbers, that probably means it's a merged package. You can't edit these in quite the same way as standalone packages, but we'll talk more about that later.
The first tab is "Textures." This is where you'll find the files you need for recoloring, but there are also a few things you can fix here to help improve your CAS experience. See that "Catalog Thumbnail" section? If you notice that only one gender has a custom thumbnail, you can export the thumbnail, switch to the opposite frame, and import it. If there are no custom thumbnails, you could even make your own and add them. Another easy fix you can make here: you know how some CC turns your Sim into a shiny plastic mannequin? That's often a specular issue. Clicking "Make Blank" may resolve this, as it will remove the broken specular. You can also remove swatches you know you won't use.
The next tab is "Meshes." Now, this probably isn't very useful to you if you're not a CC maker. But it does show you the number of polygons in a mesh if you need to keep an eye on that for the sake of your computer.
Next, you've got "Categories." This is the tab of most interest, as this is where a lot of CC goes wrong and where you can customize your experience to make these categories work for you. Before we get into it, it's important to state that you must click "Apply to All Swatches" for every single category you change! Otherwise, the change is only going to affect the first swatch.
"Outfit Type" determines into which category the content will be sorted. This can be changed (when it makes sense)! For example, I move certain types of overlays or accessories that are usually scattered all over CAS into the same category for easier and more convenient access. This helps me remember to actually use them. Otherwise, I'll forget they exist or become so frustrated searching through each category for a specific overlay that I give up. Just keep in mind that this won't fix texture conflicts. If an accessory is in the hat category because it conflicts with hats, moving it to the bracelet category won't change this. If you're curious about learning that particular skill (which requires Blender), @surely-sims has a great tutorial on removing ring/lash conflicts that can also be applied to other types of CC.
Next, you see all the flags that help the game know how to filter the CC. If it's enabled for wrong frames, ages, or fashion choices, you can disable these. But if it's not enabled for genders, ages, or fashion choices that it should be, you can also change that. For example, many accessories like socks, glasses, and hats work basically the same across both frames, but some CC creators will only enable them for one. If you do adjust gender or fashion choice availability, make sure you also scroll all the way to the bottom of this section and double-check that neither "Restrict Opposite Frame" or "Restrict Opposite Gender" is selected. On the other hand, if you have CC that's broken on the opposite frame or shows up when you don't want it to, you might want to keep these options checked.
I don't really pay much attention to the "Occult" section and often just uncheck all the boxes. If you're having trouble with items showing up in CAS for specific occult types, this might help you. Generally, I haven't run into that issue so I can't speak much to it. I also usually don't care enough to bother with all the style categories. I simply never pay attention to or use these systems, so I generally leave them alone. It just depends on how granular you want to get with your organization. But they're there if you need them and you can select as many as suit the item.
"Outfit Type" and "Sub-Part Type" are very important categories. If a certain early access creator who's been doing this long enough to know better (not naming names) always has formal wear categorized as sleep wear, you can change that. With older CC, it might not be properly tagged for hot and cold weather, and you can change that. If a jacket is categorized as a t-shirt or a sweater categorized as a brassiere, you can change that as well. You can select multiple categories here if it fits more than one. I was always frustrated by how useless these were in CAS until I started fixing tags. Now, they actually contain exactly what they're supposed to and my endless scrolling is greatly reduced.
Finally, you might want to make sure "Allow for Random" is unchecked. This is what permits CC to show up on randomly generated townies. I personally don't care for it because it just adds fuel to the bad townie fashion fire. If you want to disable (or enable) all your CC for random, I wouldn't do it file by file, though. There's a much more efficient way that I'll show you in a minute! Anyway, once you've made all your changes (and applied them to all swatches), make sure to pound that "Save" button (if you're like me, three or four times, just to be safe).
Now, take a big breath before moving on! You've learned a lot. You already have so much power in your hands. But are you ready to have even more?
3. SUPPLEMENTING S4S WITH CAS TOOLS
If you switch over to the "Warehouse" tab in S4S, this is what you'll see. Pretty confusing, right? Aside from the indecipherable strings of numbers, you can only make these changes on a per swatch basis. There's no "Apply to All" button, which makes it way more tedious even if you know what those numbers mean. This is where CAS Tools comes in clutch.
I won't spend too much time on this because I cover it in depth here, but one use for CAS Tools is that it can easily help you fix any content that might be excluding parts unnecessarily (like necklaces, bracelets, or nails). You can simply uncheck the boxes under the "Exclude Parts" section, hit "Commit Changes," and then hit "Save Package." There are some other settings here I won't get into because they're a little more complex. For now, this is the main one you'll probably find yourself wanting to change.
4. UNMERGING PACKAGES AND RUNNING BATCH FIXES
All right. Back to S4S. Now that we're comfortable with editing individual package files, let's talk about unmerging packages and batch fixes!
Creators will often merge, say, a piece of clothing and its accessory overlay into the same package for efficiency. If you want to move the accessory to a new category, merged packages make that really difficult to do. But S4S has a nifty un-merge feature. You just direct it to the package you want to un-merge and where it should be un-merged to and voila! Be careful with this, as some content may break if un-merged or separated. This is one of those cases where you definitely want to hold onto the original file in case you end up with the red and white checkerboard of doom in CAS.
S4S also has a ton of batch fixes that you can run on entire folders! I keep all my newly downloaded and unsorted CC quarantined to one folder, and I always at least run "Disallow for random" and "Update images for DX11" on this folder before allowing any of it into my main folders. There's a useful (albeit slightly outdated) breakdown of what the other batch fixes do and how essential they are here. Usually they're meant to help resolve issues introduced by new content or patches. One helpful thing about batch fixes is that running them automatically creates back-ups (Documents > Sims 4 Studio > Batch Fixes). Just make sure to delete these every once in a while or they can fill up your hard drive quickly!
I do not recommend running batch fixes on your entire Mods folder. Not only will it take an incredibly long time, but you generally don't want to run things like default replacements and gameplay or UI mods through the batch fixing process. This is where having a Mods folder that isn't just a bunch of loose files chucked into one place is incredibly important. The more organized your folder is, the easier it will be to isolate specific types of files for batch fixes (or, as it happens, do game troubleshooting like the 50/50 method).
5. UTILIZING S4S's CC BROWSER & CHANGING CAS DISPLAY INDEX
Scroll back up to check out the home screen of S4S. See that "My CC" button? If you're not already using these to view the contents of your CC folder, you should be - because it's a game changer. I know some people prefer other file organization programs, but I've found that nothing works better for me actually being able to see (and edit) CC than this. Again, you might have to wait a while for the CC browser to load, especially if it's the first time or you've added/reorganized a lot of CC, but you should see everything in your Mods folder pop up on the left side.
When you click a package file within one of those folders, it'll pull up the same preview and settings we saw earlier. But this view is especially useful for a few reasons. If you're trying to edit a bunch of files, it's quicker and easier to move through them here than if you were to open each one independently. You can also easily delete files you decide you don't like the look of, and if you simply need to get your CC folder in any semblance of order, this is a good place to start. You can't move files or create folders in the program itself, but you can at least see items without going in game. You can make edits to merged packages in here too. (Just keep in mind that "Apply to All Swatches" in this case means all swatches in all packages contained in a file. You'll have to go swatch by swatch if you don't want this.)
But the biggest secret in the CC browser is its ability to batch change CAS display index (@vyxated has also made a tutorial on this). A lot of you are probably wondering what this means. Basically, the display index determines how far up or down the catalog of items in a category an item appears. In other words, you know how some CC creators' content is usually all lumped together? This is what they use to achieve that. As a player, you can use it too - to basically organize CAS however you like. The problem is it's a pain to change the CAS display index of items individually. You have to do it in Warehouse, which means you have to go swatch by swatch. This is impossibly tedious. The CC browser gives us another way.
Right click on any folder within the browser and you'll see the two options above. They allow you to change the CAS display index for everything in that folder. You can get even more precise by using the "sorted by package name" option. As an example, let's consider my clothing folder. I label my folders according to the clothing subcategories in game, so when I batch change, for instance, the display index of the t-shirts folder sorted by package name, this allows t-shirts to all appear together in CAS but also allows for creator organization within, which is very satisfying visually, I must say. It doesn't always work perfectly, but it gets pretty close.
Here's another example with hair. Again, I've got the packages sorted into folders by subcategory, and you can see how all my bun hairstyles appear together, (mostly) sorted by creator.
So what does this process actually look like once you click the "Change CAS Display Index" button? Good question! First, you confirm which folder you're editing and where you want the back-up to go. You shouldn't have to make any changes here, so just click "Run." Then you'll get a pop-up asking you to enter the value you'd like to change the CAS display index to.
How do you know what that number should be? Another good question. @adelarsims has made a post listing the display index numbers for various CAS categories. Basically, these are the maximum numbers given to vanilla content, so you want to choose numbers higher than those. But that's not all you have to consider. If you're organizing on a more granular level like I am, you'll also want each subcategory to have a different display index number. That way, when you're viewing an entire CAS category at once, say, bottoms, all the various types of bottoms will be neat and well-organized, making for much more enjoyable scrolling. As you can imagine, keeping track of these numbers gets a little dizzying. I have a Google Doc where I've got the ones I'm using listed. You can see a couple screenshots below, but here's a link to it in case you want to use it as a base. (It also tells you what categories I sort certain overlays and accessories into, if you're interested in that.)
Anyway, let the batch fix run, check to see if everything seems right in game, then delete those back-ups once you no longer need them (they really do pile up). This is, of course, an insanely time-consuming project, but if you can get past the initial pain of sorting all your CC, setting aside time once or twice a month to do it with newly downloaded files helps you stay on top of things. I usually don't. And then I suffer when it catches up to me.
But the organizational possibilities are truly endless! Combining CAS display index with recategorized accessories has improved the efficiency of my CAS experience so much. Here are just a few examples. I've got all my hair accessory overlays in toenails since it's an underused category. All accessory tops have been moved to the right wrist category. Hair color overlays are in body scars - dye in left leg and hairlines in right leg.
Okay! I think that's all I wanted to cover in this post, and it's certainly more than enough. If this level of organization isn't for you, no worries. But I've found that it's cut down my CAS time significantly and made me reach for items I hadn't been previously, so I have a feeling others might benefit from it too, even if you take a slightly less comprehensive approach. I've recently undertaken a similar project with build/buy CC, although there are some restrictions (such as no CAS index display numbers). If enough people find this one helpful, I might write a guide about some of the methods I've used there as well. And by all means, if you have any questions, please ask!
