Human: How do you build a homemade sandbox? Assistant: 
Building a homemade sandbox is fairly simple. You will need some wood, plywood, and sand. Start by cutting the pieces of wood to size according to your desired shape for the sandbox. Then attach the pieces together with screws or nails. Make sure that all surfaces are sealed properly so that no sand escapes. Finally, fill the sandbox with sand until it is about 2 inches deep. Place a piece of cardboard or plastic underneath the sand to help keep the sand in place.