We go for walks and ride bikes.

I cool my Mesa home to a cool 80 degrees in the summer.

When I lived in Japan for 8 years, I walked and rode my bicycle a lot in 90+ degree temperatures with as much as 100% humidity. 20,000 steps is a short walk in Japan. My home in Japan does not have central AC or central heat, like most other home owners in Japan. I do have a few mini splits but we never use them.

The key is to stay hydrated (with water) and don't push yourself too hard. Stay away from caffeinated drinks and alcohol.