So, you just corrected your paint imperfections via polishing, and now you want to form a barrier against the elements in the air. What to do? SEAL and/or WAX your car.

A sealant can be seen as an artificial, manmade alternative to wax. Sealants tend to provide much longer durability because of their manmade materials, but the finish can sometimes be less "warm" in comparison to a vehicle that was waxed with a carnauba-based product. Meguire's NXT paste wax is actually a sealant because it's main ingredients are high-tech polymers. A true WAX is a carnauba-based paste...carnauba is the main ingredient, as well as rich oils to enhance the wet-look appearance. Most sealants are able to be layered, depending on if they do not contain any abrasive materials within the, while waxes are able to be layered. Some waxes and sealants tend to demand a "cure" time before the next layer has to be reapplied. Some sealants, such as Klasse Acrylic glaze, works best with a sister product (in this case, Klasse All in One). Furthermore, some sealants can be topped by wax. Typically, I would seal and then wax, but I do believe some of gotten away with the reverse of this. There are all sorts of different sealants and waxes to choose from these days, some are easier than others to apply, some last longer than others, etc... To set a simple foundation, in terms of waxes, P21S and Pinnacle Souveran are regarded as some of the easiest to apply and remove, and achieve excellent results (lower longevity though). Optimum Spray wax (carnauba-based) has left an incredibly slick surface to my Crossfire, and it last a couple months too. Collinite 476S wax is much more difficult to apply than the previously mentioned waxes, but it is regarded as one of the longest-lasting products on a paint surface too, and I think it still delivers a nice shine. On the sealant end of things, my personal favorite is Menzerna Full Molecular Jacket. It is a water-based liquid. UPP paint sealant, Klasse Sealant Glaze, and Meguire's NXT are all other well-known sealants, NXT being the hardest of this group of sealants to apply and remove. Even before a sealant or a wax, a paint cleaner like Klasse All in One or Meguire's paint cleaner wax works well to enhance gloss (All in One) or fill-in swirls (Meguire's paint cleaner). Be careful though, paint cleaners have chemicals that will remove waxes that are currently on the surface, that's why paint cleaners can't be layered and should be used before applying a sealant or wax. In terms of application, a simply microfiber applicator pad or foam pad works just fine by hand. I wax/seal by hand. P21S by hand is so easy. Some waxes/sealants/paint cleaners require that you immediately buff-off what you applied (Klasse All in One, P21S), while other products like Klasse Sealant Glaze and Megiure's paint cleaner should be applied to the whole car and then buffed-off. At this point you should take a microfiber towel and remove the residue by hand. If it is difficult to remove, a shot of quick detailer should make removal easier. To make things even easier, I use the Porter Cable 7424 and the pad that comes with it to remove the wax by putting a microfiber bonnet onto the pad.