The simple answer here is knowing your road rules. All too often our instructors are spending hours instructing drivers on the road rules they should already know. To pass the assessment you need to put in an almost perfect drive. The small number of people who fail the assessment usually do so because their road rules are not up to scratch.
For example, do you know how to indicate at a roundabout? How many times does your indicator have to flash before you change lanes? Which lane do you turn in to when turning from a single lane road to a dual lane road?
If your memory needs refreshing on these, go to the Department of Transport interactive quiz.