To find out if you need an alignment, first check each tire and look for uneven wear patterns. The problem with this method, however, is that if you can see a wear pattern like the ones listed below, it may be too late to save that tire. This is why it is a good idea to have your alignment checked periodically.
A wheel alignment cannot be done on a car with loose or worn front end parts. The technician will first check for worn parts and inform you of any problems before beginning the alignment.
The best type of wheel alignment is a four wheel alignment. Many cars today have adjustable rear alignment settings, but even for cars without adjustments in the rear, a four wheel alignment will allow the technician to identify any rear tracking problems and compensate for them with adjustments to the front.
After the wheel alignment is finished, you should drive the car on a straight and level road and check that the car goes straight and that the steering wheel is in the proper position with the spokes level. If you notice a problem, take the car back and have the technician drive it and fine-tune the alignment settings.