For people who are scared about "being bad at sewing" here are a couple concrete ways you can be "bad" at it (and what the consequences of that is). I still sometimes make these mistakes and i've been sewing since i was seven.
***Forgetting to add seam allowance. ***
For some projects this is not a big deal and it'll just turn out a bit smaller than you intended. For other things, you will be crying and kicking yourself about expensive wasted fabric.
Beginner Advice: Just don't start out making things that use expensive fabric. Make some cheap shit first to practice, like a muslin pillowcase.
Beginner Reassurance: Even if you fuck this up, and you cry and kick yourself a bit, it might not the end of the world. You can always add an extra panel of fabric to make up the difference -- the real trick is figuring out how to do that in a way that looks like Intentional Design so no one else ever notices you were covering up a mistake. (This is something that even really experienced sewists do all the time -- you might have a piece of fabric in your stash that you bought years ago without a project in mind, and now you've figured out what you want to use it for, you discover that you don't have QUITE enough. So you adapt. Easy.)
***Not sewing in a smooth, intentional line***
For some projects this is not a big deal. For projects where it is a big deal, with most fabrics you can always remove the stitches with a seam ripper and try again as many times as it takes until you're happy. (The fabrics that don't tolerate this are ones with a coating, like pleather or leather, where if you poke a hole then it stays forever. Some really delicate fabrics like satins and fine silks (and sometimes knit fabrics as well) also don't like to be sewn multiple times, but you can usually rub the surface gently or dip it in water and flatten it to dry to get the holes to ALMOST close up.
Beginner Reassurance: Woven cotton loves you and forgives you and wants you to succeed. Cotton is friend. Friend cotton. Smooch it.
Beginner advice: Trust me, you don't want to sew on that tricky shit anyway. Satin is for masochists who don't take their own advice. Love yourself, stick to woven cottons until you feel confident. Also! Pins will help you sew in a straight line because they'll hold the fabric neatly together. Also, you can use a washable fabric marker to draw the seam lines on with a ruler. If you're VERY VERY VERY new to sewing, I would suggest getting a piece of trash fabric (if you can find a ratty old bedsheet at a thrift store, that's a GREAT thing to practice on), cutting a piece about a foot square, drawing a loooong wobbly meandering line on it with marker or pencil, lots of curves and sharp corners. Then sew along that line with your machine, aiming to get the needle perfectly through the line. This will help you practice manipulating the fabric around curves and corners.
Further Advice: Keep your hands flat on top of your fabric on the "table" part of the sewing machine, rather than picking up your fabric with your fingers and moving it around. Just shift it gently with your palms.
***Fabric shifted while sewing and left a gap where the needle didn't go through both layers of fabric***
Hey! What did I tell you about using satin! Put it down and walk away! It is too treacherous for you, traveller! Friend cotton generally doesn't do this to you.
Beginner advice: Use pins or fabric clips and this won't happen
Beginner reassurance: You can always seam-rip the fucked up bit and try again. <3
***Thread keeps fucking up and getting tangled and snarled on the back of the piece (machine-sewing edition)***
Don't panic, this is not a you problem. You haven't done anything wrong. This happens because every sewing machine has the devil in it. Super normal and happens to everyone.
Beginner advice: Remove the thread from your machine and re-thread it, both the top thread and the bobbin. Test it on a bit of scrap fabric to see if that fixed it. If it didn't fix it, try re-threading again and pay close attention to make sure you're doing it right (don't put the bobbin into the bobbin holder backwards, for example). Test again. If that didn't fix it, twiddle the tension knob a bit. If that didn't fix it, open up the part of the machine where the bobbin goes and try blowing the dust and lint out. If THAT still didn't fix it, turn the machine off and go have a cup of tea or a nap. If that STIIIIIIIIILL didn't fix it, replace your needle, it is old and blunt.
Beginner Reassurance: I'm holding your hands while I tell you that this is the exact process of troubleshooting you will be using for the rest of your sewing hobby no matter how good you get. Professionals also do this.
***Thread keeps fucking up and getting tangled and snarled (handsewing)***
Also not a you problem. The thread just has too much twist in it.
Beginner advice: Just hold up your project and drop your needle so it hangs free on the thread. Run your fingers down the length of it to loosen the twist, the same thing you'd do with the cord of your hair dryer or the vacuum cleaner when it gets twisty. Some people use a little beeswax to coat the thread to help it behave. I've never used that, because just letting it hang and untwist in the air works fine for me.
Beginner reassurance: This is normal, just one of those things. You're not bad at sewing.
***Sewed things together with wrong-sides together instead of right-sides together***
Happens to the best of us, especially if you are sewing while tired and bleary. Just undo the seam with a seam ripper and try again.
Beginner advice: If you immediately make exactly the same mistake a second time, this is not your fault. This is just a sign from the gods that it's time for a break (all sewists know about this sign, it's a very normal omen). Go to bed, or go eat something.
Further advice: If you're making this mistake while well-rested and well fed, maybe your pattern or your fabric is just weird. Try sewing it with a very wide basting stitch, check your work, then sew again with a proper seam. It will at least save you time on ripping it out if it didn't work right again.
Beginner reassurance: You're working with friend cotton, right? Then you're fine, you have basically as many chances as you want. :)
***Seam looks bad when I'm looking at the piece inside-out***
Does it look okay from the outside when you turn it right-side-out? Then you have succeeded.
Beginner advice: You don't even have to fix this unless you want to. If it's a functional seam, who cares what it looks like inside out? (If you really care, your next step will be to watch some youtube videos about SEAM FINISHING, which is one additional step to make the seams look nice and tidy even inside-out.) ALSO, ironing helps. Iron your seams flat with the right sides of the piece still together just the same way you sewed it, and then fold the two sides apart and iron the seam open, gently pulling the fabric apart as you go so it gets REALLY nice and flat. On curves this is going to take some practice. Just don't do things with curves for your first couple of projects. Make a pillowcase.)
Beginner reassurance: It's ok to have an ugly seam, especially as a beginner. No one's going to check the inside unless they're a sewing nerd, whereupon you should bashfully tell them, "This is the first thing I ever made," and they will explode in adoration and praise. Sewing people are like this because we are all a little bit crazy. Every sewist i've ever met remembers VIVIDLY the mistakes they've made while they were learning and the radical self-forgiveness it took to continue learning. A very good sewist is one of the nicest people you will ever meet, because they have made Ten Thousand Mistakes, processed their upset, and kept persevering. They WILL praise your ugliest nastiest most fucked up cotton pillowcase, and they will tell you that you should be really proud of yourself. They will tell you some of the mistakes they've made. They will probably say, "No this is so good, this is way better than the first thing I made when I started!"
***I made a thing but it doesn't fit right.***
Too big? pinch it closed and sew another line. Too small? Rip the seam and add a panel.
Beginner advice: Measure twice, cut once.
Further advice: Oh, and before you do any cutting or sewing, be sure to pre-wash your fabric on HOT (if you're using cotton; you're using cotton, right? Other fabrics might need something else) so that it can do all the shrinking it's going to do.
Beginner reassurance: There's ways to fix every problem, you're not bad at sewing because it doesn't fit right. If you only knew the number of times I made a thing and it didn't fit right.... Ho hum, try again!
There are of course other ways to fuck up, but you have to be AMBITIOUS to hit those, and really those are more like... subcategories or more specific flavors of these general ones?
Anyway yeah. Go play with some cotton, fuck around, make a pillowcase. Pay attention to what you're doing and check your work vigilantly at every step. You will be fine. <3
