Prepare your mould: Choose a mould that suits the size and shape you want, something tall and solid works best. Spray the inside with cooking spray or coat with petroleum jelly to prevent sticking. Cut a piece of rope or leather and knot both ends. This will formyour door stopper’ s handle. Mix your cement: In your mixing container, combine 1 part PPC Cement to 2 parts sand. Slowly add water and stir until you get a thick, pourable consistency, similar to soft peanut butter. Mix thoroughly to remove any lumps.