I'm happy with my process.
1.) Rain-x all glass surfaces (any local autostore)
2.) Foam cannon (autogeek.net)
3.) Clay bar and lube (SONUS/ Autotopia)
4.) Klasse All In Wonder (Autotopia)
5.) Klasse Sealant Glaze (Autotopia)
6.) ZAP Auto-Glass cleaner (any smudges, does not hurt RAIN-X)
5.) Your preferred wheel cleaner / tire dressing
After two days of doing all that, all I need to do is shoot it with the foam cannon, agitate the suds then rinse off and it looks brand new, until about 8 months later when I have to refresh the AIO and SG
Check the video below on how to use a claybar. Use it wrong and you will scratch your paint like never before.