Have a good plan for how you and the instructor are going to communicate while flying. For example, make sure you have a clear-cut word or phrase ("YOU TAKE IT!") that indicates you want the instructor to take over RIGHT NOW and not try to talk you through a recovery. And maybe a different phrase ("A LITTLE HELP?") when you want him to maybe just suggest a control input or help you with orientation.

Might also be good to have a specific goal in mind for the first day of flying.. like taking it off yourself, doing 5 complete patterns around the field without help, or even landing it yourself.. and then declaring victory when/if you accomplish that and not getting too cocky and agressive and ruining the fun day by trying to do too much.

Just some thoughts. Good luck and have fun!
-Greg