More in Outdoors
Drive 20-inch pieces of rebar into the corners of the square as well as along every foot inside the frame (Image 1). Make sure the rebar is securely in the ground and sits below the edge of the frame.
Run 4-foot pieces of rebar horizontally between the vertical rebar. Tie together with steel metal wire. This will make a grid (Image 2). Cut wire with wire cutters.
For extra reinforcement, add wire mesh or matting. Cut pieces to fit inside the form. Tie to the rebar grid with wire.
Pour concrete inside the frame (Image 1). Tamp down the concrete so all holes are filled; you don't want any spaces inside the form. Smooth off the top with a trowel. Tap forms while concrete is still wet — this releases the concrete from the forms while drying. Let dry overnight (Image 2).