Mist your plug with a coat of mold-release spray. Partall #2 is by far the most popular for fiberglass molds. Buff the spray well with a buffing pad. Apply four more coats in the same manner, with each coat being thicker than the last.
Spray a layer of gel coat onto the plug and allow it to cure for at least two hours. It may take up to four hours before the coat is fully cured.
Wet 1 ounce of chopped strand mat by dipping it in distilled water, or brushing the water on. Lay the mat on the surface of the plug, overlapping each piece slightly.
Apply the resin with a bristle roller. Coat it evenly. Use an aluminum roller to force the resin into the mat, and to smooth out the surface. Allow it to cure until it's hardened, and apply four additional layers.