|I don't do this so much any more, but I used to have a terrible time managing yardage and cutting out pattern pieces. It was so bad with a particular purple panne that I had to scrap the project before I had sewn the shoulder seams.
For large pattern pieces, like pant legs or a skirt, I cut off the yardage to 2-3 inches longer than the pattern piece. I know it requires a bit more fabric to do this, but after the panne disaster, I decided it was better to waste up to a third of a yard on a project than 3 yards of fabric because the cutting was so bad. I recommend 2-3 inches extra because I couldn't cut on the grain (or it wasn't cut on the grain at the store), and my first rough cut might be 2-3 inches shorter on one side than the other. Once I have the smaller piece, I have a much easier time finding the grain.
For smaller pieces, I will rough cut, at least, 1/2" bigger all around. If you have a rotary cutter, you can go smaller, but I need 1/4" to cut with sizzors, and if I didn't get the grain right for the rough cut, I need the wiggle room.
For knits, I might rough cut the big pieces twice. That is, cut the smaller yardage piece, then cut the piece out with an extra 1/2" all around because I manage to stretch my knits during cutting. The 2nd rough cut helps me make sure that my knits haven't unstretched smaller than the final fine cut.
Perhaps they teach this or something similar in a sewing class. I don't recall it from mine 25 years ago in high school. It isn't in any books that I've seen, and it took me several years of sewing and bad cutting to figure out.
The key to accurate cutting is practice. Just like everything else, you are going to make mistakes along the way and there may be some terrible fabric tragedies. The good news is that you will get better at cutting. I just make a panne skirt without rough cutting, and it was easy.