if you’re staring down that looming heat wave and you don’t have ac, or your ac can’t keep up:
put your feet in a tub of water.
just regular tapwater. if you don’t have a bucket or washtub you can use, run a few inches in the bathtub and pull up a chair to the side of it.
this got me through a summer in a sunbaked attic apartment with no AC, in minneapolis, where highs in the 90s are pretty much guaranteed for at least a couple weeks every summer. it was at LEAST 110 in that apartment every day of that hot stretch. i cannot overstate how much soaking your feet helps.
you can also fill a plant mister from the cold tap and mist yourself.
Another tip if you need just a quick, brief cooldown - run your wrists under cold water! This saved my ass working in a hot haunted house in the Midwest when summer decided to bugger off late some years. Also, plenty of popsicles!