I don't prewash. I use Mary Ellen's Best Press, which is a starch alternative, before cutting. I don't use steam. Remember, a *bleeding* fabric is not the problem. The problem fabric is the one that picks up those loose dyes!!! And shrinkage is your friend!! When you do a less than perfect quilting job and then throw the quilt in the wash and it comes out puckered just a bit it'll hide all that less than perfect quilting.