I used to prewash and steam iron everything till I realized I really like the puckered shrink look and feel. Also if you are allergic to the fabric you might want to prewash it with something like ALL free. There is something in there to make it more stiff and sometimes I react to it. Now I often have mixed fabric some washed and some not in the same quilt. Bad girl, I know! Having this stifner in it does make it nicer to cut with.