Changing a flat tire is not a difficult task. Before you begin, check to make sure that the vehicle is not on an incline and that the emergency brake is on. Then, gather the following necessary items from the trunk of the car: spare tire, jack, lug wrench, and a block of wood. Next, place the block of wood under a tire to prevent the vehicle from moving should the emergency brake fail. After removing the hubcap, use the lug wrench to loosen the lug nuts on the hub of the flat tire. Do not remove the lug nuts at this time. Next place the jack in an appropriate position and jack up the vehicle to a point where the flat tire is free to rotate. Now, remove the lug nuts and the flat tire from the wheel. Then, place the spare tire on the wheel and screw the lug nuts on, but do not tighten them. Finally, slowly lower the car with the jack. Once the tire is grounded, tighten the lug nuts with the lug wrench and replace the hubcap. You can now remove the block of wood and return all the items used to change the flat to the trunk before driving away.