I use 3M Scotch masking tape. I read somewhere here in this forum somebody said, "After I have the tape in place I brush on clear coat over the edge of the tape". I'll do just that when I get to that part. If you look at the part I painted for practice, I did not do that, so some black slipped under the tape. The main thing is to let the paint cure for at least a week so the tape won't lift the paint as you remove the tape.
Nick, I posted this before I read your post and it's almost the same thing you said. Thanks!