Just because your jeans have holes in them doesn't mean you have to throw them away!
This is probably the first thing I ever crafted. I had my favorite pair of jeans, just like everyone else. Well, they got holes in them where my thighs rubbed together because I wore them so much. Rather than throwing them away, I decided to cut them where the holes had developed and wear them as shorts. Now they are my favorite shorts!
All I did was cut the jeans where the holes had developed. If your holes aren't suitable as guidelines for cutting, cut them about an inch longer than you want them to end up.
I folded mine over on top about an inch. That way they look rolled. I ironed and sewed them in place. Because this was back before I was really proficient with a sewing machine, I used a zig-zagged stitch to distract from the crookedness of the line.