Measure the length and width of the area to be terraced, as well as the difference in height from the lowest to the highest point.
Divide the final height of the terraced garden by the number of terraces you wish to complete. If the top terrace is to be 8 feet high and the number of terraces is four, each terrace will be 2 feet in height.
Divide the final length of the terraced garden by the number of terraces. This will determine the lateral depth of each terraced area. For best results, each terrace should be of equal length and width, however if the manufacturer's directions prohibit tall side walls, the side walls of each terrace may also be inset to form a series of U shapes sitting within one another.
Sketch a rough drawing of the number of terraces, and note the length and width from earlier measurements as well as the height of each terrace. Each terrace should comprise three sides, with the back blending into the top of the hillside. Determine the number of stones or wood timbers needed based on the manufacturer's size information for your desired materials.
Dig a trench at the base of your first terrace level along all sides to the depth required by the manufacturer of your materials if using masonry products, or to half the height of one piece of landscape timber if using timbers. The trench should be slightly wider than the terracing materials.
Firmly pack the soil at the base of the trench with a soil tamper. Check your work often with a level to ensure that you are tamping the soil evenly.
Place timbers or masonry terracing materials into the trench. If using timbers, drill a hole through your timbers and insert a spike or pipe through all layers and into the ground below. Continue to stack, overlapping joints, until the predetermined height is reached. If using timbers, use spikes or pipes to join each layer together at the corners and at each joint.
Shovel soil in and around the trench at the base and tamp firmly. Move soil from the back of the terraced area to the front until the area of the terrace is level.
Dig an additional trench for the front wall of each additional terrace to be added, building up the side walls as you go. If your terrace is created as a series of U shapes, dig trenches for the full U shape of each terrace wall.
Plant with grass seed or garden plants as desired.