You don't need guesswork. You need to understand how the test is marked, where learners go wrong, and what you must do to pass.
They fail because they're not test-ready. There's a difference between being able to drive and being ready to be assessed on it. The Driver Assessment Tool tests your understanding of the exact categories the examiner marks.
If you understand how the test is marked and what examiners expect, you give yourself the best chance of passing first time.