Flex the mold as you would an ice cube tray and peel it away from your new stepping stone. Paint the stone if you wish and finish it with a clear acrylic over-spray. Humidity and temperature will affect setting times. Design your stepping stone on paper before you pour the cement, so you can be sure that everything will fit. Include the date somewhere on your stone.
Molds are reusable.
A vinyl mold holds 8 lbs. Be stingy when adding water. If you use too much, your stone will take forever to cure - or may not cure at all. Cement may cause skin and eye irritation. Try not to breathe cement dust, and always wash your hands after touching cement.