To make the Ice IFC letters, first I used super sculpey to form the letters. After baking them, I built a mold box with acrylic boards and hot glue. I used Oomoo 25 silicone rubber for the molding compound. Don’t use glass with this stuff. I used a sheet of glass as the base and it was very hard to get it off. Anyway, it was my first time making a mold with this stuff. I think the letters turn out pretty well.