The following is my (somewhat) simple recipe for best overall results in vehicle appearance:
At least twice per year---I like early spring and early fall---do a full paint detail including deep washing, followed by clay bar, followed by thorough rinse, followed by paint correction with DA buffer and a good-quality light compound (such as Meguiar's Ultimate Compound), followed by paint sealant (optional) and finished with good-quality wax (such as Collinite 845, since it's so easy to use and last a long, long, long time).
At least once per month, do a deep wash and follow with a quick detailer spray and quick spray-on wax (again, I like Meguiar's products such as the Ultimate Qwik Detailer and Ultimate Qwik Wax).
At least once per week, do a rinseless wash (I like Optimum No Rinse Wash & Shine since it's very easy to use and extremely effective---you mix it in a bucket and you do not need to drag out a hose at all to wash the vehicle).
Take 5-10 minutes daily to do a wipe-down with Meguiar's Ultimate Qwik Detailer spray.
It may sound like a lot, but other than the twice-per-year paint correction procedure, it's very easy to maintain outstanding results.