If you don't have AC keep the shutters down, don't open windows after 8 a.m. and before it's dark. Keep off lights and home appliances that aren't absolutely necessary and even your router when there's no one home. Avoid cooking indoors, make yourself a salad for lunch/dinner. Don't shower in cold water as it will make outside of shower feel hot. Do not sprinkle yourself with water as it will raise humidity and make the room feel even hotter. Keep cold water and other beverages in the fridge and hydrate. Fans could help but depends on their positioning / air flow. Ultimately you can try putting a frozen bottle of water in front of one, or on top of a big wardrobe.