Applying wax to a vehicle preserves the paint job, protects the exterior from damage caused by dirt and debris and just makes the car look better in general. In order to keep a vehicle looking like new, you need to wax it every so often. However, recommendations for the intervals between waxing can vary from once every month or so to annually buffing the car.
Waxing your car before winter is a great way to protect it from harsh weather, as wax creates a protective barrier from the cold air, snow, road salt and other debris. This seals in the paint's oils, which are designed to prevent oxidation. When winter comes to a close, you might find you need to apply a new coat of wax. With all the snow, rain and other things coming in contact with your vehicle, it's very likely much of the wax has worn away.
If you're not sure whether your car needs to be re-waxed, there are a few ways to find out. Next time you wash your car, keep an eye on how the water behaves on the surface. When the water beads and runs off the car, this means there's still a decent coating of wax. If it doesn't do this at all, you'll probably need to grab a rag and get waxing. If you're still unsure, wait until the car is dry. Then take a clean cotton towel and rub it across the surface, applying a decent amount of pressure. If it makes a squeaking sound when you do this, chances are the previous wax application has worn away enough to warrant more.
Once you've decided to take the plunge, you'll need to decide which type of wax you want to use. There are spray-on waxes that are effective for new vehicles with pristine paint jobs. They are fast and easy to apply, and you don't have to wait for them to dry before wiping them off. However, what goes on easily also comes off easily, and you may need to reapply a spray wax more often than other types. There are also liquid and paste options, which offer their own benefits as well. Liquid waxes are good for cleaning and can offer a high-gloss finish, but are challenging to put on evenly and buff out smoothly. Pastes go on easily, but their effectiveness may not be as strong as liquid waxes.