Rototill the ground to a depth of 4 inches. Remove all large debris from the site to make space for proper root development.
Collect a soil sample from five locations on the site of your future lawn. Mix all the soil in a plastic bag. Submit it to your county cooperative extension service for a nutrient and pH analysis.
Broadcast the amendments and fertilizers recommended in the soil report you received from the lab. Incorporate everything into the top 4 inches of the surface with a rototiller.
Rake the area to a smooth bed. Push a lawn roller over it to firm the ground and expose uneven areas. Transfer soil around the bed to raise sunken spots and lower elevated sections.
Sow the grass seeds with a spreader. Apply half from north to south and the other half from northeast to southwest, providing complete seed coverage. If installing sod, lay the pieces on moist soil. Stagger the sections side by side, leaving no gaps between two pieces of grass. Use a knife to cut and fit sod around irregular areas, such as driveways and flowerbeds.
Water the bed at planting. Irrigate the seeds 4 to 6 inches below the surface. Soak sod with 1 inch of water. Maintain the lawn area hydrated until the grass roots are firmly rooted in the ground. In general, established grass needs water when it begins to wilt. Besides irrigation, follow the care practices recommended for mowing and fertilizing the grass species you chose. Most grasses require 1 lb. of nitrogen per 1000 square feet two to three times in the growing season, for example. When mowing, remove no more than the top one-third of the blades.