Lots of shade, a misting area, and block ice not cubes in their waterer and frozen fruit treats. The local supermarket you can buy a bag of frozen strawberries for .99 cents. Lots of ventilation in the coop too as I insulated the roof bays to shield any heat transferred down from the roof. Apply common sense too, during heat spells provide a place if they chose to bath. Check them during the heat of the day to make sure nobody is in distress and dip them in cool water(not cold) to bring their temp down.