Baby its HOT outside. If you aren't under a drought warning and are still haven't changed your front lawn into a vegetable garden (Hey its all the rage right now) then your going to want to water it. Right?
Make sure you water in the early morning. This allows your grass time before the hot sun comes up to absorb the water and keeps the water from magnifing the suns rays which can burn the grass.
Along with this tip goes make sure you don't cut your grass shorter then 3 inches. The taller blades will shade the ground keeping it roots cool and moist longer. It will also inhibit weed growth allowing you to skip that environmentally poisoning weed killer. (Hey if its designed to kill something its a poison!)