Scotchbrite pad, dishpan scrubber, hand full of gravel..... Being 100% clean is the biggest factor.
Just remember to scuff AFTER you aply the window masks. I ruined one of my best paint jobs with that dumb mistake!
A thin coating of ShooGoo after the paint is fully cured does wonders for longevity.
You can find it in Walmart's shoe section. There is a million and one rc applications for the stuff.
I know about not scuffing the windshield areas but am surprised that you guys don't scuff anymore. Everywhere else I've seen recommends it so is it the paint being used that makes a difference then? Or is it that the scuffing doesn't really add all that much to adhesiveness?
Not that I want to scuff, seems like a pain in the ass. I'll just shoot lighter and with more layers on a super clean body. Thanks for the shoo-goo tip as I was going to ask what you use to seal the paint to resist scratching but anything I could use that sprays on instead? Automotive paint sealer maybe? I assume it needs to be hard but flexible (like shoogoo) to avoid cracking etc.