I try not to buy ahead nor do I cut ahead. An idea pops in my brain or I see something I want to make I try to control myself in buying material until I am half way through the project I am working on. I bought a lot of green material a couple of years ago with an idea in mind for a quilt and I have lost interest. I have all this green fabric and it looks ugly to me now. I am using it up gradually but I hope I have learned my lesson of buying too far in advance. I will sometimes cut my scraps into 2-1/2" squares but mostly I just wait until I am ready to start thinking about the next quilt.