Try to time your overseeding two to four weeks before the first killing frost. If seeded early your permanent lawn will compete with the new grass. Cut the existing lawn slightly lower than normal. Rake the yard to remove grass and leaves that have not decomposed. Annual ryegrass is often chosen because of its affordable price and quick rate of germination.
Perennial ryegrass is more tolerant of cold, disease, and drought.
Use a drop or rotary spreader to disperse the seeds. To assure that the seeds come in contact with the soil, lightly drag a rake over the area. You may fertilize about a week after the seeds germinate. Do not mow until the grass is about 3 inches high. Follow the application with a thorough watering.