The need to change a car tire can happen anywhere at anytime. With punctures and flats it usually happens at the most inopportune moment in the most inconvenient place, like a city traffic snarl - in pouring rain.

Initially you need three things. These are:

1. To be cool.

2. To have a properly inflated spare tire, a car jack, a wheel brace and something to get your wheel cover off, like a screwdriver.

3. To have wheel nuts that have not been over tightened.

In fact, it's a good idea to try and loosen the wheel nuts first. If they really are too tight there is no point in continuing. This is becoming a regular problem nowadays and it's a good idea to ask mechanics not to over tighten nuts and screws when you are having your car serviced. It's technically wrong anyway to over tighten and it sure doesn't help when you are miles from home and trying to change a tire.

If you are able to loosen the nuts then here is the drill:

1. Ideally the car should be parked on a hard, level surface, off the roadway. Don't try jacking up your car on a slope. It won't work. If on soft ground put a paver or block of wood under the jack but be careful and never go under the car.

2. Get everyone out of the car. Make sure the ignition is off. Put the handbrake on and put the car in gear.

3. Remove the wheel cover and loosen the wheel nuts.

4. Place the spare tire nearby and under the car. This will help prevent damage if the jack collapses.

5. Place your jack in position and jack up the car until it's high enough to take the wheel off and to put one with an inflated tire on. Know your jack. There are various types and they are used in various ways. This is something you should know about in advance.

6. Take off the wheel nuts. A cross-armed wheel brace is best. Put the nuts in the wheel cover so you don't lose them, especially if it's dark.

7. Take off the wheel gently.

8. Put the spare tire on firmly in place and hand tighten the nuts back on.

9. Tighten the nuts a little with the wheel brace.

10. Lower the car, remove the jack and fully tighten the wheel nuts.

11. Snap the wheel cover back on and put the faulty tire, jack, brace and screwdriver back in the trunk.

When you drive away with that nice feeling of successful achievement and suddenly the steering starts to wobble, don't worry. It's probably because your spare tire has not been properly balanced. You can get it done when you get your puncture fixed.

Spare tires are usually neglected things. They sit forgotten in people's trunks for ages. It's only when there is an emergency that people remember them. In fact, whenever you are having a tire change and balance, it's a good idea to include your spare tire in the treatment.

A couple more tire tips:

If you find a nail or something in your tire, don't pull it out. This may quickly deflate your tire. The tire may run for ages with the nail in it but when you have time take it for a check-up.

If you have one of those teasingly slow punctures, you may not have to change the wheel. Try pumping some air into it and maybe it will get you home or to a service station.