Simply place your mold on a sturdy base (a few paper plates or a small pan) and fill it with water almost to the top. Carefully place it in your freezer and allow it to freeze completely.
Simply pop the piece out by gently holding the mold with your thumbs on top and fingers on the bottom of the mold and flexing it out and up. Place in a clean plastic bag immediately if you want to save the piece (s) for later and place it back into the freezer.
Using bottled water works best for crystal clear pieces or cubes.
Remember not to top off your mold with water to allow for expansion.