Bring your UK photocard licence. If you have the old paper licence, you also need a valid passport. Your instructor’s car must be insured for the test, roadworthy, and have L plates (or D plates in Wales) plus an extra interior mirror for the examiner.
The test starts with an eyesight check — read a number plate at the required distance — and two vehicle safety questions ('show me, tell me'). One of those is on the move.
Faults, in plain English
A driving fault is a small error. A serious fault is something that could be dangerous. A dangerous fault is immediate danger. More than 15 driving faults, or a single serious or dangerous fault, is a fail. You can still pass with a handful of minors if the drive is otherwise safe.
Eat, drink water, and do a short warm-up lesson if you can. Nerves are normal. A good instructor will have already put you on the real test routes.