| Care of Paint
The way that you keep a paint finish looking new is to have a cleaning routine that avoids scratching the surface. The best cleaner/wax to use is the one that has the finest abrasives and the deepest shine. I haven't tried them all, but I always go back to the plain, green inexpensive liquid Turtle Wax. It may not last as long through washings but I think it shines the best. Everyone has a favorite, that's mine.
But, the key to a mirror shine is the removal of fine hairline scratches, the ones you can see only in the bright sunlight. These are the ones you've put there when you've rubbed grime across the paint surface when you wash or clean the bike, or just simply rubbed against it. Just wiping the dust off the bike with a clean cloth will cause them. Your wash rag is the major source of the problem, so start your wash from the top and work down toward the dirtier surfaces. Rinse a lot.
The key to a museum-quality shine is in the technique used in the application of the cleaner and wax. In particular, you need to avoid making more fine scratches as you clean and polish-out the old ones. So to save you the time, here comes the tip from 40 years of experience...
THE TIP
Go to the pharmacy/chemist and get a roll of white cotton batting. You know, the material they wrap around your arm when they put it in a cast. Now, tear off a small piece, wet it with water, and squeeze it till it's only damp (important). Now, use it to apply your favorite cleaner or wax. Tease it apart frequently to reveal a fresh clean cotton matte surface, and throw it away when it gets slightly dirty with any embedded grime (most important). Polish with a well-laundered old cotton T-shirt. The roll of cotton will last for years and so will your new paint.  | 
Shazaam!
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