I buy on sale and stock up on basics like neutrals, black and white. I'll buy at least 2yds. If I see something I really like and want it for backing I might buy 7 yards. I like to buy in color families too. For instance, I'll look for blues and browns on one trip, yellows and reds on the next. I primarily like scrappy patterns, so lots of fat quarters work for me as well. When I do shop for a color controlled quilt I always buy extra to add to my stash.