Show up on time, listen to your senior residents especially with respect to the clinical pearls, follow through with assigned tasks, be honest and truthful, don't cut corners, don't take criticism personally, and read about procedures ahead of time so that you have a basic idea about the steps. The procedures are taught on the job as residency is essentially an apprenticeship. The part we can't teach an intern is integrity and work ethic. You'll be fine.
Good luck!