Making a Silicone Mold and Concrete Casting | QUIKRETE ...
Mix the concrete, following the instructions on the bag, and pour the mix into the mold. Tip: Make the concrete a little more watery than usual to help it pour easier into the small mold. Step 14 Tap and vibrate the mold to remove as many air bubbles as possible and let cure. Step 15 Remove the plastic ring from outside of silicone mold. Step 16