On travel days, try to do it early so you can get hooked up and have your air conditioner running before the 4-6pm peak heat of the day.
If you're going to be away from the RV for a while and are at a FHU site, open your cabinets to keep them from trapping the heat (if your RV is already at a comfortable temperature inside).
Don't leave your awning out if you're going to be away from the TT, winds can come up without much warning when storm cells move through an area.
Having thermometers inside and outside the TT can help you determine if it is a good time to run a Fantastic Fan (if you have one). My rule of thumb is if the outside air is 3 or more degrees cooler than inside, I start with that rather than my air conditioning.
Use the pillow style overhead vent insulators.
When driving I feel better using a lower gear and higher RPMs rather than lugging the engine or let the automatic transmission hunt around too much.
Sit in your TV (with it's a/c running) and go over your pre-departure checklist after any stops. Even having a short list (door handle, steps up, slide-in) helps when you've been rushing to get out of the heat.
Have towels or some other fabric you can throw over the seats in your TV so they don't soak up solar heat. Also a cover over the steering wheel can be smart.