First you need to know how to crotchet, of course. But once you've got that down, this video has your back.
Wait. I got an idea for the next cheap POS DS game: Crotchet Mama. It will use 2 stylus' instead of one. You start off first with drink coaster covers, and gradually get up to doing a wooly, itchy blanket that you give to your grandkids.