|Most students I have worked with will sew for years and never make a single buttonhole or zipper!
Now, they are amongst the more difficult skills to perfect along with collars, welt pockets and godets, to name a few.
The best thing to do is spend a few hours practicing this skill over and over again.
Do it before you start to sew up a garment that has requires these applications ~ You'll be so glad you took the time to do this.
start off with a sample from something you have in your closet so you have a reference point. Study how is constructed. It's also best to do some research on these techniques so you can learn the "secrets" that make it easier/better looking. Don't just rely on the pattern instructions as you will get minimal information.
When I was in design school, we were not allowed to use pattern instructions in our first sewing class. I never use them for my own personal sewing as I know better ways to make something.
However, for a beginning student, they are necessary.