wash with a NICE wash mit, cheapies will scratch, well EVERYTHING you touch to your paint scratches it, but you wont always notice. swirls scratches ect. every thing that contacts the paint leaves a mark whether it be microscopic or not, its there.
so a good wash mit is key. clay bar EVERYTIME you wax. before waxing of course. claybaring removes contamination that you cant always see. bugs and other such particles. lubricate the bar and just rub it all over the truck as if you were waxing and the bar is the applicator pad, keep it lubricated during the entire procces, youll know if its enough cause a non/underlubricated bar "grabs" and sticks to the paint, its not bad just almost impossible to do it dry. you can use water or a spray wax for lubrication. i like megiuars gold glass wax. turtlewax platinum series is good too. wax is more or less a preference with all the major brands. its all good. most people dont know how to use a highspeed buffer so buffing/polishing is out of the question but hand polishes and glazes are a good second best.
so to sum it all up:
1) wash thoroughly with a good mit and a good sudsy soap
2) clay bar. remove heavy tar with tar remover and a towel. fold clay bar as it becomes dirty.
3a) polish (by hand or with a buffer) **this is optional**
3b) wax, liquid wax is easiest to work with, megiuars, turtle wax, zymol ect.
4) remove wax with a good microfiber cloth, terry towels leave swirls!!!! as wax builds up on cloth turn over. if streaking appears squirt the paint with a little bit of window cleaner.
5) relax and enjoy! you earned that shiny ****ing truck!