Turn off the water heater power or set the gas control to pilot
Shut off the cold water supply to the heater
Open a hot water faucet in the house to relieve pressure
Attach a garden hose to the drain valve at the bottom of the tank
Run the hose to a floor drain, outside area, or other safe drainage point
Open the drain valve fully
Open the temperature and pressure relief valve if needed to speed draining
Open the drain valve on the tank and the hot faucet together to let air in
If draining is slow, briefly open the cold water inlet to stir sediment, then close it
Use a wet/dry vacuum or transfer pump if the tank is draining too slowly
Close the drain valve when empty
Remove the hose
Refill the tank by opening the cold water supply
Keep a hot water faucet open until water flows steadily
Restore power or relight the gas heater only after the tank is full