You can use either gel or modeling paste to make your mold to cast with. You need a heavy but flexible surface to use as the base for your mold; we prefer 300-lb. (640gsm) watercolor paper (a lighter paper may warp a bit). With this technique, the heavier the gel or paste, the better shapes will hold because of the stiffer binder. Layer raised gel or paste stencils on top of a dry texture, or scrape away gel or paste while it is still wet to add to or subtract from it. Variations are endless with this technique.
STEP ONE: Spread hard gel gloss on a piece of heavy watercolor paper.
STEP TWO: Make lines, shapes or marks in the gel and let it dry.
STEP THREE: Add an edge with aluminum foil, making a box shape around the gelled paper, then pour in the plaster.
STEP FOUR: Let the plaster cure before removing the mold. It will set up in approximately a half hour.
STEP FIVE: Carefully pull the paper off the plaster once it has dried.
STEP SIX: Wait until the plaster has cured for several days (until it is bone dry) before painting it with acrylics. Seal with GAC 800.