Indian here, so experienced with hot climate.

• Wear loose cotton clothes (long-sleeved if stepping out in the hot sun)
• Keep yourself hydrated.
• Avoid soft/ aerated drinks/ soda & coffee as they'll dehydrate you. Stick to cool water, ice chips, fresh lemonade made with water, fresh fruit juices, melons, spinach-cucumber-onion-tomato salads, yoghurt,
• Eat light.
• Stick to well-ventilated rooms with good air-circulation (fans help)
• Cold water showers to cool down
• Sweating is good. It'll cool you down. This is also why Indians eat spicy food and drink hot tea even in hottest summer. Get sweaty then take a quick cold-water rinse.
• If you have to step outside in the hot sun, umbrella, hats, caps etc are your friends.
• Wet towel on the back of the neck for a quick cool down.

ETA: When it gets so hot that we lose our appetite, then our go-to meal is to mix up cooled cooked rice with unsweetened yoghurt and a pinch of salt. its variously called yoghurt rice/ curd rice/ thayir saadam / dahi bhaath / dahi chaawal . This is an easy to make & easy to diges meal that is guaranteed to cool a person down.

thayir = dahi = curd = yoghurt
saada = bhaath = chaawal = cooked rice

Good luck.

North africa here, we are between air conditioning, fans, drink water and pray it ends fastly, in my country our problem is more energetical, more demand less production.

Close the windows, curtains and shades during the day, at around 8-9AM. When it's very warm outside, open windows are your enemy.

Open windows, curtains and shades during the night when temperature is lowering.

I do construction work in Alabama. I basically bitch and complain all summer long and hate every second of it. There's no relief unless you're in the AC. I've been thinking of ordering a liquid cooled vest actually. They look weird but I'll try anything. The humidity here is killer. Sweating doesn't help like it does in dry climates. Every time I walk outside my body shuts down and I have literally no energy. I think i had a heat stroke last summer.

If someone above me tells me to go work outside all day and doesn't offer me a substantial amount of money, I tell them to go fuck themselves. It isn't worth it.

fan and cooler during dry heat, onlyfans during humid heat after rain, get cotton vest for upper body and cotton bermuda shorts, get external keyboard and a laptop stand with fans for laptop.

AZ here, Get a cheap low power desktop for work shit, it will heat up less and you'll be able to ventilate it better.

Otherwise, a/c, thermal curtains, insulated reflector layer in front of that, make sure your weather seals on your doors are good. Drink water all the time, carry water with you all the time. Good luck with all the heatwaves and welcome to the club.

Most heat gets in through windows facing the sun. I cover the worst with aluminium foil (tin foil).

Also bans all the evil rays! Pew pew pew…

Have central air conditioning in all buildings.

Have a place to swim.

I'm in the US and it was 40C (104F) yesterday, which is normal for my area. I spent the whole day either indoors or in the neighborhood pool, and it was perfectly comfortable.

Lots of fans.

Sleep during mid-day

Brazilian here, to be fair I've read so many good tricks here that I am not sure what I have to contribute, but yeah, light clothes with bright colours or white, don't dress dark as your clothes you heat up. No shoes if you can, but also not barefeet lol sandals and flip flops havaianas styles. If you live close to the beach obviously go take a swim, otherwise swimming pool or AC at home or car or go to store random stores with AC too lol. Drink cold stuff, keep hydrated. Fans, and cold shower.

Houses are built differently in hot areas. Very few windows facing south. Shutters on all windows. All windows deeply recessed. Channel the wind, ie have a deep through channel that spans across the house so any pressure differential causes air to exchange. Tiled floors. No/low insulation.

In Northern Europe, we live in sweat boxes designed for letting in maximum light and keeping heat inside the house.

In the southern US we have air conditioning everywhere. People avoid going outside except for very early or late in the day when the sun isn't on you. I try to get any yard work or anything outside down before 10am and avoid going outside the rest of the day.

Yesterday was actually a "nice" day where I'm at because the high was "only" 34C. People were outside enjoying it, but still avoided the sun and were mostly out in the morning and afternoon in shaded areas.

The one thing I don't see mentioned enough for keeping your apartment cool is to close all windows and draw all curtains during the day and open them when the temperature outside is lower than that inside (normally ~an hour after sunset).

Heat reflects off all surface, so it's not just about keeping light out.

Blinds on the outside of your windows help significantly too.

If AC isnt an option, the way Ive gotten through summers without is opening one window on one side of the building, then another one on the opposite side. Then point a box fan facing outward of one window, and do your best to seal the gaps with some cardboard or whatever you have. This will create negative pressure in the building, drawing in a bunch of air from the opposite window.

If the dew point is favorable at least, then drinking Hot Coffee and let myself sweat in front of an Electric Fan. If it is very humid, Ice on neck or taking a cold shower.

If I had to go outside or Air conditioning at the office broke, then I'd wear light clothing where sweat is easier to evaporate

Otherwise, I'd just use air conditioning and eat up the electricity cost, fuck this weather.

This stuff is unbearable, I can’t even play video games on my laptop, because it warms up very fast and the keyboard becomes uncomfortable for me to use.

There's a lot of good advice in here but I haven't seen anyone tell you to just reduce the amount of heat being generated in your home. Almost every plugged in electrical device in your home is generating some amount of heat. Esp. if they're in use.

So my suggestion to you is to flip off the power-strip or unplug unnecessary devices, and find something else to occupy your time. The consoles, PCs, the tv itself, they're all hungry devices that generate a lot of heat. Those fans people are telling you to use? They generate heat too... so while I'm not saying, "don't use a fan to stay cool", I am saying, "don't fill your home with running fans in rooms you aren't in".

When I lived in a top floor apartment in Melbourne, where it regularly hit 40°C without any air-conditioning (still unsure how that was and is legal to rent out), I would use a spray bottle of water and a fan to evaporatively cool myself, cold showers to lower my body heat and trips to an air-conditioned space like the cinema or shopping centre during the worst of it.

No mention of wet headcloths and neckerchiefs here! Get some water on that neckerchief and it’ll drip down the hotter parts of your body. A wet headcloth loosely draped under a hat or headband catches the wind and sends evaporative cooling down your back, and gives you cooler air to breathe.

There’s a reason why deserts around the world are filled with garments like the keffiyeh, pashmina, shemagh, pañuelo, and cowboy scarf. I’ve spent a lot of time in the outdoors with a kufiya from the Hirbawi factory in Palestine, they’re well-made and amazingly handy. Their story is worth reading at http://www.hirbawi.ps .

When the weather hits 40⁰ around here I might head to the cinema. They're usually really well temperature controlled, dark and allows you to get out of the sun when it's at its height. Nights when it doesn't cool down are harder.

I'm from eastern europe too, I feel like I almost died from the august 2020 heat, this year I couldn't belive my eyes seeing 37°C on the weather app last week(and continues to rise). The hail mary was fans for me, but air conditioning is something that will get harder to live without as years roll by and the temperature increases. I know I'm not the intended audience, but what worked for me was spending more time in rooms where the sun doesn't hit as much(for me it's the bathroom), standing near walls(I noticed they don't catch a lot of heat and they are not too cold to lean on), every few hours try to splash some water on your face and neck and maybe(I don't know if this works, didn't try it) towels that are wet and were left a bit in the fridge(I'd avise much caution with temperature change to avoid termic shock, for the towel too not be too cold and the body too warm). Hydrate and avoid going outside mid day as much as possible. Summer gets easier when you work in an air conditioned office, but until then, good luck and drink water.

Ceiling fans should be set to warm weather mode (there should be a switch on the base which changes the direction of spin), you want them to ~~pull hot air up (so the lower edge is the leading side)~~ push cool air down, had it backwards

Cotton/baggy clothes: cotton loses all insulation properties when wet so its nice on a hot day, baggy clothes are generally more breathable

Self-misters are fine, but do not use humidifiers, lower humidity = faster sweat evaporation = cooler you

Drinks w/ ice and/or icecream: cold stuff inside your body will cool you down

Avoid the outside at 1-2pm: this is usually the hottest part of the day

For your laptop: buy a desk fan and point it right at your laptop, has the bonus of cooling you down too

Here's what I do, dampen a towel and put it in the freezer. Once the towel is good and cold wear it like a cape. Looks kinda stupid but you'll stay cool.

People have already mentioned wet towels on your neck but I would add, if you can, cold wraps for your legs: wet towels around your calves.

Always humid heat, days above 35 degrees have increased a lot. Have to use an AC all summer long... Prayers to those who have to work outside.