"Back in the Day", you'd get some tape and a piece of Masonite and do it all by hand. Or, if you wanted to be really snazzy, you'd get a piece of Plexiglas, put the tape on the back in a reverse image, spray paint it all, then remove the tape and illuminate it from behind for a really fancy look. Keep in mind the real thing didn't look that way, it was usually pretty basic, at least the vintage ones.