Always ask what you can do to help another nurse if you aren't busy.
Never ignore an alarm, even if it's not your patient.
Make sure all your lines are in order and labeled.
Clean up after yourself and your patient for the next shift (they are your colleagues too).
Clean up after your teammates if they are slammed.
Ask lots of questions, and listen to the answers.
Take time to learn everything you can about your job and your patient so you build trust in your autonomy.
Have a good attitude; it's infectious!
One more, don't take anything personally! If another nurse, therapist, MD or family member is short with you, assume it is because s/he is under stress. Watch for ways you can help out (sometimes helping out is leaving the person alone for awhile).