Prevent water runoff from your sprinkler system. To reduce evaporation, water the lawn in the early morning or evening. Avoid watering during the heat of the day or when it is windy. Install a trickle or drip irrigation system for a slow, steady supply of water to the plant roots. Water only when needed.
Frequency depends on plant and soil type.
One inch of water a week, including rainfall, is all your lawn needs. Water root areas of your plants to establish hardiness. Use native and adapted plants when landscaping your yard. These plants usually require less care and water. Consider installing plants that don't require water once they are established.