Fertilize your lawn to provide your grass with the nutrients it needs to stay lush, dense and healthy, thereby warding off the weeds and diseases that may plague less healthy lawns. Water your lawn immediately after fertilizing. This helps to prevent chemical burns to the grass and also carries the nutrients down to the lawn's root level where the grass can best use the nutrients.
Wait for a clear and dry weather period. If you're unsure, consult the National Oceanic and Atmospheric Administration's National Weather Service for a forecast.
Sprinkle your lawn slightly with water to evenly moisten all of the surfaces of the grass.
Apply the fertilizer to your lawn according to the guidelines listed on the fertilizer's label, as potency varies widely by product.
Water your lawn with enough water to moisten the soil to a depth of 1/2 to 1 inch. To determine when you have watered the lawn to this amount, the University of Florida Extension Service recommends placing straight-sided cans in several places around the lawn. When water reaches the proper amount is in all cans, you can turn off the sprinkler.