I sat my nav exam last month. Take your time to read the information for the first question. Work out the full flight plan for the whole lot of the journey. Remember that the wind will change on the different legs to try catch you out. Once you have completed the flight plan double check it to make sure.
Its important that you get the plan spot on as 1 wrong answer will hamper you for a few questions as they are all linked to it.
Agree with above comments. Make sure you plot accurate!!
Good luck