The first watering of newly installed sod is the most important. Begin watering immediately after installing new turfgrass. The first watering establishes how well the grass will perform for years. It is advised to lay a section of fresh sod down and then start water on that section as you start to lay another section of sod down.
Apply at least 1 inch of water so that the soil beneath is very wet (You will want the water to "squish" under your foot if you step on it). For the next 2 weeks, apply at least 1/4 of an inch of water a day (more will be necessary on hot or windy days). For the remainder of the season, apply at least 1 inch of water a week 2 to 3 days apart (this may vary between seasonal changes).
Tips: Make sure water is getting to ALL areas of your lawn. Corners and edges are easily missed and tend to dry out faster than the center of your lawn. Areas near homes or buildings tend to dry out faster as well because of heat reflected from the building. Water will evaporate quickly when it is hot or windy as well.
Runoff may occur on sloped areas so pay special attention to the tops of hills or sloped areas.
If you notice your sod turning a gray-blue cast it is need of more water. Also, footprints that remain in the grass after 1/2 hour or more is in need of water - footprints will disappear within a few minutes on well-watered lawns.
Inspect your lawn frequently to determine watering requirements.