Turn off lights when not in a room.
Only run appliances when necessary
Unplug appliances when not in use.
Wear a sweater instead of turning up heat.
Use fans instead of turning down air conditioner.
Engage in activities that do not involve electronics.
Rely on sunlight instead of artificial light.
Replace old appliances with newer more efficient models.
Insulate your home.
Make sure windows and doors are well sealed.
Use LED bulbs if available, or compact fluorescent light bulbs (and dispose of properly!).