I started as a new grad in the ED a little over a year ago. The two most important things I would say for you to incorporate into your practice are to ASK QUESTIONS and DELEGATE TASKS.
Ask any question that comes up. Ask the attending, the resident, the grizzly veteran nurse who terrifies you..ask the social worker and the interpreter and the phlebotomist. People know you're new and they should be happy to help. I still ask a million questions. "Forgive my ignorance, but..." "Pardon me, I've never heard of ...".
As for delegation, it is essential. If a co-worker asks what they can do for you, give them something to do. In my department, everyone loves to start IVs. It's a solid bet that if I ask someone to do it, I'll get three volunteers. Don't be afraid to delegate VS and other errands to techs and CNAs. That's part of their job and if you're too busy doing things beyond their scope, ask them to do it. The flip-side to that is to BE PROACTIVE in returning the favor. You'll get a lot more help if you're seen as not just a taker. Got a few free minutes? Offer to help someone else.
I'll toss in a third key item. It may be the most difficult, but it'll really help you progress. And that is to TRUST YOURSELF. Yes, you still look up meds. You still look up policies and procedures. But you know a lot. You can speed things along for patients by keeping in close communication with doctors, and making relevant suggestions. Think a social work consult will be needed? Get on the horn and give SW a heads up. Suspect the doctors may be missing something? Bring it up to them. If your facility has nursing protocols for orders and such, get used to using them.
Congrats on your job! I think ED is a great place to start!