LIke everyone says...preference, preference, preference. I always have but lately this fabric I have been getting at the fab store (50/50 cotton/poly) has been really stretchy and thin. So I take it as it was cut, baste stitch the side (salvage) closed and then wash it. Helps it not to stretch and to stay in shape during the wash. I have discovered...100% cotton only for quilting tho..at least for larger areas. the 50/50 doesn't work so well!