I just graduated, so am not an RN yet (taking the NCLEX in two weeks ), but in my program some of the things that separated those of us who did well in clinicals from those who did not are:
1. As others have said, be willing and eager to learn any and everything the hospital staff and your instructor can teach you
2. Make sure you are proactive about asking to do things...no one will ask if you want to do something, you have to take the initiative. I always asked the nurse I was working with if s/he was expecting any interesting or new procedures with any patients that I could watch or participate in. If another had something interesting coming up and I was all caught up with my own patient I would ask if I could observe.
3. Don't ever, under any circumstances, do things that you are not allowed to do, even if a nurse at the hospital offers to let you and not tell your instructor. You could get in serious trouble, even get kicked out of your nursing program, if you don't follow the rules.
4. If you are at all unsure of what you are doing, ask.
5. If you are all caught up and having nothing to do for your patient right that minute ask the nurse or CNA or whoever if there is anything you can help with. There is always a lot to do if you are willing to do things like changing bedding, or helping to ambulate someone to the bathroom, and the nurses and CNAs I have worked with have all appreciated the offer of extra help.
6. Do not ever feel you are too good to do something. There was one student in my program in particular who thought that cleaning up patients and emptying foleys were beneath her. The nurses and CNAs on the floor did not like her much (shocker) and she was always upset that the rest of us got to do a lot of things she never got to do.
Best of luck!