I am so sorry!
Here's what I learned: If you normally use nipple waterers you should add simple water dishes on hot days - apparently the panting interferes with their ability to drink from the nipples. Plus they can dunk their wattles while drinking which will cool them, too.
A mister is great in dry heat, basins with water nd bricks to stand on and cool off, large iceblocks in their water to keep it refreshing longer. Water melon is great. Electrolytes in their water during the heat of the day, no ACV. If you find a chicken panting very hard and becoming lethargic, dunk it in a bucket of cool (not icy) water, so the water reachsa just their belly, wait until they stop panting. Repeat if heavy panting resumes. It is a good idea to check on them every 30 minutes, at least until you know that your chickens are using the options you gave them to cool off and it is working.
Yes and if all else fails bring them in the house...