Another thing to keep in mind is that the old turtle was right, slow and steady wins the race. Know your limits, and stay within them. Just because I could tear a roof off like an adrenalin fueled mad man for 12 hrs a day when I was 20, doesn't mean I can do that when I'm 50 (or 35 as it turned out). Over time, your body grows accustomed to performing at a certain level. For many of us, that level is lower than it should be because as we've aged, we've learned to work smarter and not harder and now spend more time on our rear ends than on our feet. So if your body isn't accustomed to hard work in the heat, go slow and pace yourself, and maybe try doing it with a little more frequency to stay more acclimated to it.
I don't like the heat, never have, but I also always seem to be out working in it. Stay hydrated. Water is best. If you can add some occasional electrolytes with Gatorade or something similar, that's fine, but your body NEEDS the water a lot more than it needs the electrolytes (primarily salt). You can do hard, strenuous work outside in 95 degree heat for a couple of hours and not really need any more electrolytes. Obviously, if you are going to work outside all day long, electrolytes should be considered, but they are still secondary (by a LOT) to water. Personally, if I'm not planning on drinking AT LEAST a gallon of water (8 bottles) while I'm working, I don't worry about the electrolytes, and if I'm planning on drinking more than a gallon, I take some king of small snack which helps with both the electrolytes and blood sugar. A large percentage of the world still survives without air conditioning or Gatorade, and with minimal mechanization compared to what we are accustomed to.