If you do water your lawn, check to see if your city has a watering ordinance and make sure to follow it. Always be sure not to water during the hottest part of the day (midafternoon). And if you have an automatic sprinkler, be sure to turn it off during/after a rainstorm. Few things make me more mad than seeing an automatic sprinkler going off in the rain.
These three simple watering ways will make a big difference in your conservation efforts.