Nerves are normal — examiners see them all day and mark your driving, not your heartbeat. The best antidote is earned confidence: a mock test under real conditions two weeks out, so the format holds no surprises.
On the day: arrive early, no caffeine heroics, slow breathing in the waiting room — four counts in, six out. If you make a mistake mid-test, let it go; candidates pass with imperfect drives all the time. One error only becomes fatal when it snowballs into five.