Here is a basic overview of what I do in the Level II portion of my NICU everyday:
First, I get report from the off going nurse. When she/he is done, I go through my medications and make sure I know all the correct med administration times. Then, I get started on my care. In our unit we take vital signs every 4 hours. I start on my first baby, getting HR, respirations, blood pressure, abdominal girth, etc. I do a full head to toe assessment of the baby, noting any changes I may need to bring up to the doctor or practitioners. I change his/her diaper, change his/her clothes and bedding and feed him or her. If he has any medications due at this time, I administer them. I sit down and feed them. I do this for all of my babies in the morning. As the day goes on, I relate information to the practitioners/docs about what needs to/should be done for the babies. Parents come in and call, and I attend to them as if they were patients as well. I answer any questions they may have and encourage interaction with their babies by encouraging breast feeding, and by having them do diaper changes, etc.
At a very basic level, my responsibilities are assessing the babies for any changes, administering meds, and feeding them. There is a lot more that comes with the job but those are just the foundations of being a NICU nurse.