I don't use mylar, I use laminate. I go to Kinko's and ask them to give me the heat set laminate without anything sealed in the layers. It comes in roughly 24" wide pieces (some stores have wider) and I ask them for as many feet in length as I want. It is cheaper and it rolls nicely. Not only that, I can just trace all of my designs on it and my patterns don't have to get cut up. If there are a lot of pieces for appliqué I write 1 of say 6 and so on, on each piece I cut out.