Be sure to place the faucet lever on the kitchen sink in the cold position when using small amounts of water; placing the lever in the hot position uses energy to heat the water even though it never reaches the faucet.
Drain a quart of water from your water heater every three months to remove sediment that can slow down heat transfer and lower the efficiency of your heater.
During warmer months, turn you water heater off when you're gone longer than a weekend.
If you heat with electricity and you have an unshaded, south-facing location (such as a roof) on your property, consider installing a solar water heater - they save energy and are good for the environment.
If your water heater is more than seven years old, consider buying a new one - today's models are more energy efficient, and the savings will continue throughout heater's lifetime.
Keep your showers short to save hot water - with a regular shower head, just a one- or two-minute reduction can save up to 10 gallons of water. You can also use an energy-efficient shower head to maximize savings.
New heat pump water heaters use heat from air to heat your water - and they use 30 to 50% of the electricity of standard electric resistance water heaters.
Repair leaky faucets promptly - a leaky faucet can waste gallons of water in a short time.
Take more showers than baths, and keep the showers short. In the average household, bathing uses up more hot water than any other water-related activity. You use 20 to 25 gallons of water for a bath, but less than 10 gallons during a 5-minute shower.
Wrap the tank with the proper insulation for maximum efficiency, but be careful not to cover the thermostat.