Jill you need to use a stabilizer under your fabric. You can use anything from a commerical stabilizer to tissue paper. This will help the pucking in your design. I have taught several classes in machine applique and have found that tissuer paper, double it and carefully remove it from the stitching. Also do a practice piece using several different stitches available on your machine. Mark the practice piece with the stitch lines that you like to use this as future guideline to you. I usually use a blanket stitch and have had great results with it. You can shorten or lengthen the stitch as desired. Hope this helps.