If you're lucky, you're leaving Arizona this summer for cooler weather, perhaps anywhere else with a southern latitude (since it's winter for the southern hemisphere now). If you're staying here, you'll have to encounter the 100-degrees-even-when-the-sun-goes-down type of climate. Good luck!
1. Stay inside.
Simple enough, though jobs and classes beckon you outdoors. If you can though, do not leave your home. Hibernate indoors for a couple of months to beat the heat. Work from home, pick up a freelancing gig, get your groceries delivered. Minimal contact with the desert heat is desired.
2. Camp out in the shade.
Your job didn't buy your idea of not coming into the office until October, so now what? Stay in the shade as much as you can. Since the valley doesn't have the lushest trees around and the only shade you'll be getting is from a building, perhaps invest in an umbrella.
3. Pool hop.
When you're outside, stay cool by immersing your entire body in a pool of cold water. It could be your pool, a neighbors pool, someone else's pool whom you have never met, but anything to survive the heatwave. Be careful though and leave if you are asked.
4. Carry a lot of water.
It's not enough to have water around you at all times. You need to be drinking it! It is so hot in Arizona that your sweat is evaporating away, which makes it a lot more difficult to tell how much water and salt you're losing from your body. So replenish that loss even if you don't necessarily feel thirsty. The consequences of dehydration are dire
5. Invest in a mini fan.
If you can't stay inside, afford an umbrella, too scared to check out a stranger's pool, and, well, there are no excuses for not having water... Behold the greatest invention: a portable mini fan with a water spray nozzle. Carry it everywhere you go and douse yourself in a fine mist of Phoenix tap water.
6. Eat Paletas.
The most crucial tip of survival involves food, naturally. Paletas are Mexican popsicles that are upgraded from the lame sugar rocket pops we had as kids. Paletas have real fruit, will cool you down, and hydrate all at the same time. That's a triple whammy for sure.