I started PP w/ copy paper, switched to tracing paper and now only use freezer paper. With freezer paper, you first crease all the lines of the block, then press the fabric to the paper. When you sew, you go right next to the fold and never actually sew thru the paper. After each piece is sewn on, you press carefully, without getting the iron on the shiny side. This holds your pieced fabric to your pattern until the whole block is finished. Carefully remove the freezer paper and you can use it over again, sometimes 7 times, before it isn't shiny anymore. You can order freezer paper that will go thru your printer, online. With this method it's not necessary to lessen your stitch length, but I usually stitch w/ 2.5, since I generally have small sections of pattern = 1/2" wide.