Open windows on opposite sides of the house to create a cross-breeze. Open windows and use fans to let in cooler night air. Close them in the morning to trap the cool air inside.
Use light-coloured, reflective curtains or blinds to block out the sun. Install shutters or outdoor blinds to prevent the sun from hitting the windows directly. Put heat-reflective film on windows to reduce heat gain.
Plant deciduous trees on the south and west sides of your home. They provide shade in the summer and let sunlight through in the winter. You can also grow climbing plants near windows to block direct sunlight.
Apply reflective or light-coloured coatings to your roof to reduce heat absorption. Consider using a green roof with vegetation to provide insulation and absorb less heat.
Use evaporative coolers (swamp coolers) if you live in a dry climate. They use water evaporation to cool the air. Place cooling mats or pads on beds and furniture for a cooler surface.
Use light-coloured paint and decor to reflect heat. Use thermal-backed drapes and blackout curtains to block out the heat.
Open windows or vents at higher points in the house to let hot air escape and draw in cooler air from lower points.