|I use rolls of polyethylene (clear plastic) from a hardware store or building supply store. This is sold in three weights. The lightest is the cheapest, but I find the medium weight easier to handle. The plastic is about 100 inches wide, folded in half on the roll, I'm not sure how long. A roll costs less than $10. To copy a pattern I use weights to keep the palstic in place and an overhead projector marker to trace and add comments such as the date, elastic length, who it was made for, how much I lengthened etc. I prefer Staedler Lumocolor permanent pens, but these can be hard to find. I have found it best to use black, as blue and red seem to fade. The plastic pattern pieces are easy to fold, and the roll is easy to store. I don't pin them, but use weights for cutting out as well.