this is my method
1st i sprayed multiklen multi purpose cleaner and then wipe...
2nd i sprayed autowax polymer sealant and then wipe also kekekeke
3rd and lastly i sprayed autowax silicone gloss...and then wipe again laa...and the result is great! tested on my Kancil's headlamp:) and also on harrier..it work with glass lamp too...and also on W210 it worked too:)