Soaked headdresses...or soaked hats, handerchiefs under hats, bandannas...all good. As in winter, head temp. regulates body temp. If you can keep your head cool the rest of your body will benefit. If you have to be out working in the heat, having enough water available to douse head, as well as drink, is a must.

Kiddy pools...very helpful...very cheap. And easy to fill and MT (pref. onto trees and flower beds). With something cool and pleasant to drink in hand, a soothing soak in the evening in a kiddy pool is delightful (assuming you dont have the real thing).

Aside from heavy water intake, there is nothing quite like a large slice of very cold watermelon for cooldown. 110 every day here and if I have to be out in it for long, and internal temp. starts climbing and wont come down, leisurely meal of watermelon works every time. I don't use an A/C but a bowl of ice cubes placed in front of a portable fan is locally effective.

Hope your heatwave breaks soon!