Smallest patches go on first. The foot patch doesn't quite fit the description of the smallest patch, but the ends are smaller than the other patches, so I put it on first. I lay the sail out flat and pin the foot patch into place. I try to get everything to lay as flat as possible, then trim up any excess I have on the patch. Some people use double-sided sticky tape to hold the patches in place for sewing, others use fiberglass reinforced tape to both hold the patches down and prevent stretching, but I just pin 'em down. It all works.