Step 1: Remove the bottom plate concealing the burner door and sight glass.
Step 2: Mark the temperature control, so you can return it to the original setting.
Step 3: Set the temperature and regulator dial to pilot lighting.
Step 4: Make sure your spark igniter is functional. Click it a few times, and check for spark through the slight glass.
Step 5: Hold down the pilot switch and spark the igniter until the pilot flame is lit. Continue to hold the pilot switch down for 30 seconds to 1 minute. Once the pilot switch is released, the pilot flame should stay lit. If it goes out, the thermocouple, temperature cut-off switch, or gas control may be at fault.
Step 6: Turn the regulator valve to the on position. Turn the temperature dial back to the original setting. You’ve successfully lit your water heater!