Some people burn the grass to de-thatch it. This works well, but in many areas, local ordinances prohibit urban and suburban burning. Check your local codes.
Minimum to maintain health and color is 1"-1. 5" per week, so you would want to water a minimumof 3 times a week at 1/2" per. Since the grass is still green, it's still photosynthesizing, so you can still apply fertilizer, a good watering just before freeze-up in fall, to boost their moisture reserves