If you have the time, try to tab your copy of the FAR/AIM (and make sure you have a current version). You can put the plastic sticky tags in commonly used sections to make it easier to find a specific reg or other info in the AIM instead of having to spend minutes searching through the table of contents or the index. Remember to relax and not rush your speech or mumble, etc. Examiners pay attention to how you present the info too. Hopefully your CFI has been giving you tips, but reviewing some public speaking habits can give you the confidence to express the things you know properly, and enable a student (or examiner for now) to understand what you're communicating.