Good luck - remember you will most likely feel more nervous than you look - also remember that noone can know everything so don't worry if you get asked a question you can't answer. The examiners will probably want you to pass, so they will be looking for evidence that you do know a bit about your topic. They are not looking to catch you out and find out what you don't know (in most cases). Try not to be nervous, this time tomorrow you could be celebrating - try and think of that. What a weekend that would be. Positive attitude;-)