In mid spring, dig the upper 2 inches of soil with a shovel to loosen it and break up hardened dirt that will block grass roots from growing. Pull out any rocks and limbs as you find them.
Rake the loosened soil to smooth and level it, without packing it back down. Spread 1 to 2 inches of fresh potting soil or compost over the loose soil. Rake the potting soil or compost lightly to level it.
Evenly toss grass seed out over the area by hand or use a seed spreader to distribute it, using an average of 3 pounds of grass seed for every 1000 square feet of land you want to cover. Use a larger amount if it is recommended by your seed brand's packaging.
Spread a light covering of straw over the seeds and soil to protect them from rain and wind, but do not use so much straw that you block sunlight from reaching the seeds.
Water the soil with a sprinkler or hose to soak the soil thoroughly without creating runoff. Repeat watering every two to three days or as often as necessary to keep the soil from going dry for the first month.
Add additional potting soil or compost and grass seed to any bare patches in early to mid fall, and continue regular watering. Repeat the following spring if your grass still has bare patches or the grass that has grown is thinner than desired.