Yes, it is essential to tape off the area before painting to ensure that the lines are straight and even. The tape will act as a guide to help you paint straight lines without going outside the intended area. The tape should be applied carefully and should adhere well to the car's surface. You should also ensure that the tape is not left on for too long to avoid damaging the paint. It is recommended that you use a high-quality masking tape that will not leave any adhesive residue or damage the car's paint when removed.