It's too hot now. What can I do to cool it down? The premise is that I can't say I want to buy an air conditioner.

There is no air conditioning in summer, and some simple methods can also make your room cooler. 1, reasonably open and close doors and windows. Open the doors and windows for ventilation in the morning and evening when it is cool, and close the doors and windows during the day, especially at noon, to isolate the invasion of outdoor hot air, and draw a light curtain to block the sun and reflect thermal radiation, so that the room becomes cool. 2, balcony greening, courtyard greening. Some data show that planting grapes, morning glory, Parthenocissus tricuspidata and some flowers and plants on the courtyard balcony can reduce the temperature of the attached wall by 5℃ ~ 14℃ and the indoor temperature by 2℃ ~ 4℃. 3, indoor use of fans and water evaporation cooling. For example, after wiping the floor indoors with a wet mop, turn on the ceiling fan to evaporate and absorb heat; You can also put a basin of cold water (preferably ice cubes) in front of the fan, which can reduce the indoor temperature and increase the air humidity. 4. It will make people feel comfortable to clean up the room in summer, so that there is more space in the room. Avoid indoor clutter, which not only makes people feel stuffy and breathless, but also makes people feel irritable.