Cut one 8-foot cedar board in half using the skill saw. Cedar is used because it naturally resists rotting when in contact with the moist garden soil. Avoid pressure-treated woods because the chemicals used in the process can leach into the soil and harm your plants and possibly your health when you consume them.
Place two 4-foot boards parallel to each other 8 feet a part. Lay two 8-foot boards on either side, producing a box shape.
Screw four wood screws into each corner with the drill, joining the boards together.
Place the wood box in an ideal location for your garden and fill with soil to the top. The ideal location for a garden receives at least 8 hours of direct sunlight a day and provides drainage for excess water.