Turn off the lights. It's a myth that switching lights on and off uses more energy. Use natural light when possible.
Don't leave appliances on "standby." Standby settings can still use over 40% of the energy needed to power the product (e.g. computers, TV, DVD players). Turn electronics off when not in use, especially overnight and during long breaks.
Turn off your computer monitor if leaving your computer for more than a few minutes; the monitor uses the majority of a computer's energy.
Unplug chargers once electronics are fully charged. Your chargers will continue to consume energy when they are plugged into an outlet, even after your device has been unplugged.
Turn down your thermostat, or use a programmable thermostat to only heat your home when somebody is home.
Turn your water heater down to the warm setting for regular use and to the vacation setting when you are on vacation.
Keep showers short. This will save both water and energy, since using less hot water will decrease the amount of energy your water heater consumes.
Use a lid when heating water. A lid will decrease the amount of heat that escapes from the pot, saving time and energy.
Warm food at a low temperature. Once things are boiling, turn heat down.
Only boil as much water as necessary, whether for making pasta or tea. Heating excess water equals wasted energy.