The best advice I can give is to be polite, listen, and try not to worry. The instructors want to see an improvement on your grades throughout the weeks so don't be too downhearted if you start shakily as long as you improve through each lesson.
They are looking for improvement at each lesson and a capacity to learn. Anything you can do to ease the capacity burden is a bonus. It is worth having an idea of what the different instruments are but other than that there is not a lot you can do. During the course don't get shedded as that is quite a big black mark if you fly when hungover. In all just remember it is 13 hours free flying and try to enjoy it.