Hi, this is what I have done on a snowman penny rug. After I finished sewing the top and bottom pieces together, I sewed the penny's on with about 3 stitches done with invisible thread.Just run the thread thru the backing and come out at each penny. I also attached them side to side with a couple of stitches. Makes everything nice and secure. Hope this helps. You can also join a group on Yahoo that is about working with wool and woolfelt.