19. Use those ceiling fans
You might think that ceiling fans are just for hot weather, but that’s not the case. Yes, in the summer they can cool you off by pulling hot air up and away from you, cooling you off. Most of them can be reversed, though — either by changing a setting or by turning the blades down. When reversed, they can gently send warm air (which rises and tends to accumulate at the ceiling) down to you to warm you up.