Deep and infrequent beats short and daily
Roots grow toward water. Watering a short cycle every day keeps moisture in the top inch of soil, so that is where the roots stay, and a lawn with roots an inch deep has no reserve when a hot week arrives.
Longer, less frequent cycles push moisture deeper and pull roots down after it. A deeper root system is what carries turf through the part of summer where nothing you do at the surface helps much.
In practice that usually means fewer days per week with more time per zone, not the reverse.
Water before sunrise
Early morning is the correct window for two separate reasons. Evaporation loss is far lower than midday, so more of what you paid for actually reaches the root zone.
And the blades dry as the sun comes up, which matters because extended leaf wetness is the condition fungal disease needs. Evening watering leaves turf wet all night, which is how you end up treating for disease in a month you should not have to.
Finishing right around sunrise gets both benefits at once.
Cycle and soak on clay
Brazos Valley clay does not absorb water quickly. Run a zone long enough in one go and the back half of that run is sheeting off toward the street rather than soaking in.
The fix is cycle and soak: split the run into two or three shorter cycles with a gap between them, so water has time to move into the soil before the next one starts. Most modern controllers do this natively.
You can see whether you need it. If water is running down the driveway partway through a zone, you are past the soil's intake rate.
Read the lawn, not just the calendar
Turf tells you before it is in real trouble. A blue-grey cast rather than green, blades folding along the midrib, and footprints that stay visible after you walk across it are all early signs.
Those symptoms mean water now. They do not mean water every day from now on. Adjust and watch what happens over the following week rather than committing to a schedule based on one bad afternoon.
Different zones will also differ. Full sun in front and shade behind the house should never be on the same schedule, and if they are on the same zone, that is a design problem worth fixing.
Beds and turf are not the same
Established beds generally need less frequent water than turf, and mulched beds hold moisture much longer. Running them on the turf schedule overwaters the plants and wastes the difference.
If beds and turf share a zone, one of them is always wrong. Splitting them is one of the more worthwhile irrigation modifications on an older system.
Watering restrictions can also apply locally during dry stretches. Check with your water provider for current rules before setting a schedule, since those change year to year and we would rather you get that from the source.