People aren't good at hydration, at least I wasn't, so at the risk of self promotion I have an iphone app called Max Hydrate - https://apps.apple.com/us/app/max-hydrate/id1575744883#?plat... - that calculates how much you should drink to stay hydrated. It's based on research and the most important parts are free.

I had thought about it mostly for working out and athletes, but perhaps in warmer temps it has more general applicability. I've learned older people often suffer from dehydration without realizing it.

It has a WUT test to test for dehydration and uses your sweat profile to suggest hydration products. There are a lot of options these days beyond Gatorade and Pedialyte.

Most people don't get enough salt, so that's something to watch out for, especially if you are a salty sweater.

Snacking on canned sardines in water (and drinking the broth) seems to work well enough, plenty of sodium.

edit: Writing this comment has made me realize mixing powdered dehydrated boullion into the water would probably work quite well too. The ambient temps are so high the water is basically at hot soup temperature as-is.

I've used Pedialyte (and equivalent convenience store alternatives[0]) after cutting weight for grappling, and occasionally also to prevent (or recover from) hangovers. Very useful drink.

0. Make sure they have Zinc!