Just watched a Fons and Porter TV show, they used mylar hex templates from Brandys, you get one for the cut size and then 50 or so of the 'heat resistant' templates. What the girls did on the show, not saying right or wrong, was cut the hex out of the fabric, spray it well with spray starch, then iron fold the edges of the hex, every other one, around the template.....let dry well...then pop the template and sew. They sewed on the machine with invisible thread....can look us the episode if you want...