IMHO a float position might be difficult at first because you are so new. It might be best to start off with one floor/unit responsibility.
Some things to factor into that hopefully will help:
1. Ask questions. Don't do something unless you KNOW how to do it.
2. Keep pen/small pad of paper handy - pocket of your scrubs
3. Be professional: clean scrubs, clean shoes, be punctual, be ready to learn.
4. You can speak to anyone. When addressing nurses/doctors, etc, try to get your point across in the first two sentences. Then if they need more details, they can ask you.
5. Smile, be gracious, polite (please and thank you go a long ways)
6. Realize that not everyone is going to be nice. Patients are stressed, nurses are stressed, physicians are stressed. Don't take things personally.
7. Don't reveal a lot of personal details. This is your workplace, not hanging out with friends.
Best wishes as you start this new venture