This week's book giveaway is in the Mac OS forum. We're giving away four copies of a choice of "Take Control of Upgrading to Yosemite" or "Take Control of Automating Your Mac" and have Joe Kissell on-line! See this thread for details.
Only study those areas you are weak on right now to concentrate your time more efficiently. Get a good night sleep before the exam, then on the day of the exam, don't study at all. Just go take the test. Studying a few more hours on the day of the test is just going to make you anxious, since it's really not possible to learn anything more on the day of the test than you already know. Good luck!