1) Choose the right grass. The right grass for your yard will depend on your climate, conditions, and soil. Talk to your nursery expert about the best choices. In general, cool-season grasses survive harsh winters but tend to suffer during summer months; warm-season grasses thrive in summer sun but go dormant during the winter--and turn brown in below-freezing temperatures.
2) Water appropriately. It's better to water deeply to encourage root growth instead of watering frequently. There are not hard-and-fast rules about how often to water. When the surface soil feels dry to the touch, it's time to water.
3) Fertilize. Apply a nitrogen fertilizer in late spring and summer and be sure to water it in thoroughly. Fertilize cool-season grasses throughout fall and spring. Again, ask your local nursery person about specific recommendations.
4) Mow properly. Don't let the grass grow too long; mow when it reaches about one third taller than its optimum height.
Courtesy of Toro Wheel Horse Tractors & Riding Mowers