Spray the walls of the cement brick mold with a mold release spray. Molds are either made of plastic or wood and you need to spray them to prevent bricks sticking to their walls. The mold release agent will help you remove the cement bricks from the mold without damaging it. Apply only a barely visible thin layer of coating. If you leave excess agent on the wall, it may create bubbles on the brick's surface.
Wipe off the excess release agent from the mold using a dry cloth.
Mix two scoops of cement with a half-scoop of water. Stir it until you get a toothpaste-thickness mixture. Add additional water if needed.
Scoop the cement mixture into the mold shapes. Fill up the mold to the top to make bricks.
Bounce the mold up and down to help the cement settle in all corners of the mold. Wait 48 hours for the cement to dry. Turn the mold over to drop the brick out.