DIY Mold for Poured Concrete

Measure the length of your walkway path from beginning to end, using your tape measure. Purchase enough 12-inch hardboard siding to cover the full distance of the walkway along both edges.

Use your table saw to cut your 12-inch hardboard siding in half lengthwise so that it is now essentially 6-inch planks of hardboard siding. Lay the 6-inch hardboard siding strips along the edges of the walkway to create the width and shape of pathway you intend to create. Drive wooden stakes into the ground every 36 inches behind the hardboard siding to hold it in place.

Use your table saw to cut one length of 18-inch hardboard siding. Use these pieces to create solid joints between lengths of hardboard siding. Attach each length of hardboard siding to the next by placing a joint support behind the joint and screwing the ends of both lengths into it using your screw gun and drywall screws.

Using your concrete mold as a guide, dig out the walkway to a depth of 6 inches using your shovel. Lay the two edges of your concrete mold into the space once it has been excavated.

Cut your 1-by-4-inch board to a length about 3 inches wider than the width of your walkway. Using your screw gun and drywall screws, attach one small wooden block to the bottom of each end of the board so that the outer edges of the blocks fit between the two sides of your concrete mold. Lay the board on top of your concrete mold with the block side down and lay your level on top of the board. Slide the board up and down the length of the mold to make sure that it is completely level and that the width of the walkway remains constant throughout. Make any necessary adjustments accordingly.

Press the dirt along your walkway path down using your compactor. Place a 3-inch layer of gravel along the length of the walkway. Lay rebar and pour your concrete into the mold. Allow 24 hours to pass until the concrete has completely set before moving on to Step 7.

Start at one end of the walkway and place your shovel beneath the first wooden support stake. Lift the stake out of the ground and move on to the next. Repeat the same process until all the stakes on the first side are out. Move to the other side and repeat. Remove any remaining mold or frame pieces. With the mold removed, the concrete walkway is complete.