#simstel

1. open sims 4 studio and go into CAS. it doesn't really matter if the selected button is "Create CAS Standalone" or "Create 3D Mesh".

2. you'll be teleported to a wide selection of available CAS items in your game. you'll also see the CAS items from your owned game packs. for this tutorial, first choose the pack-exclusive item. you may navigate through the toolbar above to find whatever specific item your'e finding. press Next afterwards.

3. save your package in your chosen folder.

4. export its mesh as well as its texture. make sure the diffuse one is selected (seen just above the Export button). if you have your own texture for this specific mesh then you don't have to save its original texture. * in this part you can also add color swatches in case you forgot to choose the other colors (or you just don't like the available colors).

5. press Cancel then repeat the same steps of going into CAS except this time find an item that is BGC. also make sure that this item has the same part type/age/gender/species as your first item. in this picture you can see that i still chose the same specifications, so that this mesh and the first mesh can perfectly fit. press Next. * it is easier if you choose an item that is mostly an undergarment, such as a bra or tank top, or one that can easily be covered by your first chosen item or cc. you'll see why later.

6. save your package in your chosen folder.

7. this time we only need the mesh, as we're going to replace its texture with the one we want, so press Export Mesh.

8. open this mesh, or specifically the base-game available item, in Blender.

9. on the right side, you'll see the s4studio_mesh_(no.) files. * if there is only one mesh file, like in the picture below, usually named s4studio_mesh_1, remember the number of cuts. this can be found under the s4studio CAS tools tab, the one with the GEOM type. * if there is more than one mesh file, join all the meshes by selecting each one (shift click) and join them by pressing ctrl + j or the join button, which can be found by toggling Edit (found in left side). now that there's only one mesh, remember its number of cuts. this can be found under the s4studio CAS tools tab, the one with the GEOM type.

10. go to File and press Append. press the blend file (the exported mesh) of your pack item, then Object. then, select all the s4studio_mesh_(no.) available (shift click). press Link/Append from Library.

11. by this time you're supposed to see your model with the base mesh completely covered.

if not, like in this example, find the single mesh from your base item by toggling the eye of each mesh on the right side. you'll know it's the base mesh if any unnecessary patch has disappeared from your model when it is toggled off. 

delete the vertices of the unnecessary patches of your base mesh. there are many ways to do this. for me, i go to edit mode, right click (the outlines will turn black), press B, then go over the unnecessary parts. the selected vertices should turn orange. press X, then delete vertices. keep doing this until you achieve your desired look.

12. we should only have one mesh, to do this, shift click all the meshes (including the base mesh) and join them by pressing ctrl + j or the join button, which can be found by toggling Edit (found in left side).

13. now there's only one mesh. remember when i told you to remember the number of cuts? (step 9) check if the number of cuts are the SAME as the base mesh. in this picture, they already have the same number, so it's all good. if not, just type in the number.

14. go to File and save your Blender file. (can be saved as another file)

15. go back to Sims 4 Studio, specifically to your base game item. press Import Mesh and choose the newly saved Blender file (the new modified mesh).

16. it's going to look weird at first (like in the pic LOL) because you haven't imported the texture yet. go to Texture and import the texture of your pack item (or cc). press Save afterwards.