In that case just take it back and tell him you're not satisfied. Point out the problems and see what he says. If he's an honest guy he'll do it over... and do it right but I wouldn't expect him to tape off anything. He's a pin striper and good enough with a brush.
You could have done it better if you just spray them with red enamel and wipe it off the raised stuff with a thinner dampened rag. It's simple and if you screw it up it takes all of ten minutes to wash it off and do it again.
