Changing spark plugs is something almost anyone of reasonable ability can do, saving money over paying someone else to do it. Starting with the owner’s manual for your auto, you will need to look up the location of the spark plugs on your vehicle.
At an auto parts center, purchase the new spark plugs you will use to replace the old ones. Take your car or truck home and let it cool down completely. The spark plugs can get extremely hot. Referring back to the owner’s manual, locate your spark plugs.
Using a spark plug wire puller, or your hands if you do not have one, pull the wire from the small cap (boot) where it hooks up to the engine. Don’t pull the wire itself, or you may damage it.
Using a socket wrench, and a swivel joint or extension if needed, get a good grip on the spark plug socket. Turn the socket wrench counterclockwise until the spark plug comes free. Before you put the new one in, make sure the hole is clean, using compressed alcohol or rubbing alcohol if needed.
Using just your hand, to start with, place the new spark plug and tighten it as well as you can. When you can’t tighten it anymore by hand, use the socket wrench to finish the job. Wait! You’re not done yet. You need to reconnect the spark plug wire by attaching it to the new spark plug. After you replace the other spark plugs, you are finished!