what to do if ur mid maneuverer and a car is approaching in a narrow road?

For instance, parallel parking. I cant do it as quick and like to take my time to make sure i dont hit the curb etc. However, I always panic when theres a car waiting for me in a narrow road, i dont like holding them up. Do I just rush it and park imperfectly and ask to try again or just ignore the car and take my time?