DIY: Plywood Couch

Place two 24-inch 2-by-4 boards next to each other on the ground. Put the large surface on the ground, parallel to each other about 17 inches apart. Put two more of these boards on top of and perpendicular to them. Arrange the four boards in a square frame. Drill two holes through each corner where they overlap. Attach the boards together by drilling 2 1/2-inch wood screws through each hole.

Repeat the procedure to create a total of three frames. Stand these frames upright, spaced about 2 feet apart. Set a 3/4-by-24-by-60-inch plywood board evenly on top of them, spaced evenly so that it lines up with the front and back of the three frames. Drill holes through the plywood board every 6 inches, into each of the square frames. Attach the plywood to the square frames with 2 1/2-inch wood screws.

Position a 30-inch 2-by-4 on the back of each square frame with its largest face touching the square frame. Arrange it so that it sticks up 24 inches above the plywood and overlaps the square frame by 6 inches. Drill four holes through these vertical boards, which are the backrest support boards, and into the square frames. Attach the backrest support boards with 2 1/2-inch wood screws.

Position another 3/4-by-24-by-60-inch sheet of plywood vertically against the three backrest support boards. Adjust the board so that it is evenly spaced against the support boards and even with the plywood sheet that it is perpendicular with. Drill holes every 6 inches through the plywood sheet and into the backrest support boards. Attach the boards together with 2 1/2-inch wood screws.