Fig 1. Keep out the heat. On hot days the north and west facing windows should have the blinds pulled down.
Install ceiling and wall insulation as this can be an efficient way to get the most out of your heating and cooling equipment.
Install exterior blinds to reduce heat gain in the house.
Close windows when heating or cooling.
Use reverse angle ceiling fans to force hot air down to floor level.
Reduce your heating/cooling thermostats.
Use heavy drapes in front of windows to retain heat.