I grew up with only scrap quilts on the farm and I enjoy carrying on the tradition of totally random scraps. That said, I have found you must throw everything you have (fabric related) in the mix for it to work well. Sort of "Go big or go home" kind of theory. EX: If I am making a "blues only" quilt, I would use every blue from light to dark to blue greens/teals. If it looks remotely like a blue, in it goes! For my totally random colors quilts: EVERYTHING in and I just pick up and sew. No thinking or worrying allowed:-)