Datsss You wont need to use a razorblade. I beg to differ on the rubbing back between the colour - black - clear unless you are doing them all within a coupe of hours of each other. Most average Joe's would paint the colour and then next day/weekend do the stripes etc. You are only trying to take the little shine out of the dry paint and whatever #OOPS# you get in the paint from doing it outside.