Wash your car regularly - I'd recommend to do this at least once a month. Things like bugs, bird's dropping, or limestone dripping damage the paint leaving permanent stains if not washed off in time. When the car is clean, all the moisture dries up quickly, but when it's dirty, the moisture accumulates in dirty areas causing corrosion. At least once in a while use pressure wash - it removes the dirt from difficult to reach areas (I do this at a coin car wash station). Wash off all the places where the dirt and salt could be accumulated; for example, behind moldings, inside wheel arches, under the bumpers etc. It's particularly helpful after winter - to wash out all the salt accumulations that speed up the corrosion process.
Wax your car regularly. Wax helps to protect the paint, minimizing harm of chemicals and protecting the paint from fading; plus the car looks shiny. It takes only about 30 minutes to wax a whole car and high quality car wax stays on the car for three - four months. So far, I haven't seen a single product that stays for life time as you may have heard in some commercials - nothing lasts forever. In order to maintain protective coat any product needs to be reapplied periodically.
axing gives your car natural shine and helps to protect the paint from harsh environment. When applied to the car, the wax forms a thin transparent layer over the paint. This layer covers minor scratches, stone chips and other damages making them less visible. The wax also "seals" the paint preventing water from contact with bare metal exposed in deep chips and scratches. This helps to slow the corrosion process. However, none of the available car wax products stays permanently on your car, the wax needs to be reapplied regularly. From my observations, good car wax stays on the car for about three-four months, so if you wax your car at least every three months using a good product, you'll be OK.
If the car hasn't been waxed in a very long time, it make sense to take your car to a local detailing shop first. Or visit your dealer (e.g for an
change) and ask for one of those detailing packages they offer. What they do, they buff the car with electrical buffer using polishing compound containing a mild abrasive to remove light scratches, hard stains and other impurities on the paint, then they wax it. After your car has been detailed, you can simply reapply wax every three months or so to keep it shiny.
To wax your car you will need some good quality wax (e.g Carnauba wax), small soft sponge and clean soft cloth towel. Your car must be very clean and dry. I usually wax my car right after washing at the coin car wash, the whole process of washing drying and waxing takes about an hour.