First let me say this. With a water heater there is no way to know for sure if the power is off without a meter to test it. So do not go sticking your fingers in there until you know for sure.
Once you have removed the blue cover to your water heater element, using the meter to test for electricity is a must. If you don’t and water leaks out while there is juice, you can be in big trouble.
Once you know for sure the power is off. Turn the water off to the water heater. There should be a valve nearby, if not turn all the water off to the house.
Once you do this, you need to go to the sink and turn on the hot water to help reduce pressure on the water heater.
Then you can take the special wrench for the heating element and a large screwdriver. Let me explain. The wrench is long and has a hole on both sides at the back. This allows you to take a screwdriver and slide it into the holes. this give you the leverage you need to turn the wrench, allowing you to remove the element. Water will come out when you do this. Expect it. Just keep towel handy for the cleanup.
Once the element is removed you can replace it with a new one. It’s the same process just in reverse. Tighten the new element and clean up all water around the heater.
Turn the water back on, allowing the heater to fill back up. Once it’s full, you can turn the power back on and press the little red button that allows you to reset the water heater.
Then just replace the blue cover on the water heater, and you’re done. Enjoy that hot shower.