Lay four, six-foot beams in a square on the ground. Use three-way connectors to solidify the square. Drill a screw into each joint afterward to secure the connection. This is the base unit.
Repeat Step 1. Once the square is complete, screw in a curved bar across the center of two of the sides. This bar does not need to be very high, about one foot is sufficient. The bar will raise the tarp on top up so that rainwater slides off it. Make sure the remaining joint on the three-way connector faces down and the curved bar faces up. This is the roof unit.
Cut a plastic tarp so that it fits over the square made in Step 2. Duct tape the tarp around the square frame. The tarp should fit tightly on top of the square with raised roof.
Insert four, eight-foot metal poles into the remaining hole on the connectors on the square made in Step 1. Drill screws into the four joints to secure the poles.
Place the roof unit on top of the four poles in Step 4. Secure the roof unit with screws into the joints.