Safety First! Find a safe place to stop, out of the flow of traffic and if possible, on a straight part of road, so that on-coming traffic can see you from a distance. Also turn on your hazard lights.You will need to stop on a flat, firm spot as it is unsafe to use a jack on soft ground or on inclines.
Get all the tools you’ll need from your car:
Spare tyre (properly inflated), Car Jack, Wheel Nut Wrench, and if you have them, gloves and a torch will always be handy.
Remove the hubcap and turning the wrench anti-clockwise, loosen the wheel nuts, but DO NOT remove them. It can take quite a lot of force to break the wheel nuts free.
If your car has molded plastic along the bottom, it will crack when you start lifting the car if the jack is not put in the right place. Modern cars will have a small mark or notch behind the front wheel wells, or in front of the rear wheel wells where the jack is intended for be placed. Place the jack under the frame near the tyre you are going to change and make sure you put it where it will meet the metal portion of the frame.
Pump or crank the jack until the tyre is lifted off the ground. You need to lift it high enough to remove the flat tire and enough to put the spare, fully inflated tyre on. As you lift the car, make sure it is stable. If the car seems unstable then lower the jack and fix the problem before fully lifting the car.
Remove the wheel nuts completely and then remove the tyre. Place the flat tyre under the car so should the jack fail, your car will fall on to the old wheel.
Place the spare tyre on, taking care to align its rim with the wheel bolts, then put the wheel nuts on and tighten by hand. Then using the wrench, tighten the nuts as much as possible. To ensure the tyre is balanced, don’t completely tighten the nuts one at a time. Go in a star pattern around the tyre, one nut across from another, giving each one a full turn until they are equally tight. Don’t use too much force as you could risk upsetting the jack.
Lower the car to the ground fully and remove the jack. Tighten the nuts again and replace the hubcap. Put the old tyre in your boot and take it to a mechanic to get repaired or replaced.