How To Keep Cool At Home in 40 Degree Celsius Heat When is hot and sunny and you do not have an air-conditioning at home the following tips may help to keep you cool. 1. Keep your blinds closed. 2. Close all doors and windows. 3. Turn On Fans to create a wind-chill breeze effect. 4. Stay hydrated. Water is essential for keeping you cool during hot weather. 5. Splash water on your skin or put on a wet shirt. When it’s hot the evaporation will cool your body.