I will offer a few thoughts as a long-time desert explorer.
By no means do I count myself as some sort of expert, and other advice here may be better than mine.

1. I strongly suggest that you travel ONLY on well-paved roads. Avoid sand, dirt, and bad asphalt. You will find that the apparently "simple" act of changing a tire in 105-110 degree heat becomes are very unpleasant experience. If you ever make the mistake, as I have a couple of times, of actually getting your vehicle stuck in sand in that kind of heat, and having to dig out, you will quickly realize that you are caught in a major survival threat. The effect of that heat is much worse than most people think. Even if you have got multiple bottles of Gatorade. There's a pretty good chance you can just flake out from heat overload. Hence - travel on good roads with a good car that has air conditioning.

2. Cell phone coverage is not guaranteed in all areas, although it's pretty good in most places.

3. Forget mixing drinks. Have multiple bottles of Powerade or Gatorade with you. Ready to go.

4. Driving and scenery are much more pleasant if you time them for the early morning, or evenings. No glare. You can see nice scenery. You're NOT fighting the heat if you have a breakdown. In the middle of the day - shack up at some pleasant stopover, have some long cold drinks and rest.

5. In spite of the incredible paranoia about "bad people" in the middle of nowhere in the desert - I have yet to meet even one. And that's after 30+ years of desert travel. There are some slightly weird and half-baked "desert rats" out there. They tend to be isolationists. But they're not serial killers. They just have a hermit kind of mentality, that's all. It would probably be socially unacceptable if you just went around shooting them :-)

6. You can take a gun if you want ... but the fierce heat is your real enemy. Early mornings and evenings are you friend.

7. ENJOY the desert. It's a beautiful place! Most people never even give it the time of day - they're too busy driving to a casino somewhere.

Pete2