Hi, you have to determine how far apart the 'repeat' is on your fabric. The further apart the repeat the more yardage you need. I started a stack n whack in a class 2 years ago but never finished it, I hope to maybe this year. My first recommendation is to get one of the stack n whack books at your library and see what the directions are and what is recommended. I believe I bought 5 yards based on my 'repeat'. some of the gals in class got 7 yds, but that seems too much, maybe they just wanted to be 'safe', or use some for the backing, I don't know.