How do you paint windshields, so it looks clear where the whipers go, but dirty where they don't. Does this sentence makes any sense?

I just want to make my windshields look dirty, but don't know how...

Thanks!

Hey there

one of the main ways i've seen this done is cutting and applying a mask that covers the arch that the washer blade goes over, so that that part of the window stays clear.

Thanks, but my question was more about the colours and paint to use to make the windshield dirty, so that it looks dirty apart of the masked part, but still a bit transparant...

Try spraying a highly diluted mix of Tamiya Buff or Deck Tan (95% thinner, 5% paint) in very quick passes. Mist it on--don't let it build up. This should do the trick.