What kind of job/internship? I kinda jumped in the deep end with an ER job right out of school where I was solo after about 4 training shifts. There are a couple other more experienced vets here on SDN that have done the same thing, but I think in general most people take a more ... measured ... approach to jumping in. You'll be fine. Promise.
LIS's rules for managing emergency cases:
1) Recite "Airway, Breathing, Circulation" (or whatever variant you like) over and over and over in your head. Virtually everything else on ER you can take time to stop and think about what you're doing. Most of the cases you see are vomiting/diarrhea dogs and inappetent cats, anyway. And the work-up is so standard for those you can just recite it in your sleep. Which is how you do it most of the time.
2) Don't give direct medical orders to your techs. Instead, mumble "Hmmm.... I suppose I should do X" under your breath. If your techs look at each other - change your mind. If they look like they approve, go with it. They know more than you do anyway. Figure out which are the really good ones, and when they say "Can we do X?" just go with it because that's their way of telling you "Um, smart doctors do X." When my techs come say something like "LIS, can we put a central line in this 4 week old chihuahua so that we can actually give it the therapy you've planned" it doesn't take a braniac to realize it's a good call that you should have already made had you not been busy heating up your 3am burrito.
3) Figure out which of your Facebook DVM friends you trust and bank on them to be online 24 hours a day just to help you out. If they aren't on, repeat call them on their cell phones until they wake up, because they aren't doing their job.
4) Pick a couple action-oriented textbooks (i.e. procedures, meds, etc - not the detailed internal medicine pathophys stuff that you can spend time hunting for) that you really like and keep them close at hand. Remember, pathophys is for real docs, not ER docs.
5) Be brutally honest (in a gentle way, obviously) with your clients about their pet's condition. Don't give them more hope than they should have, because then they'll be P.O.d when their pet dies and you were telling them fluffy had a great chance. I don't sugarcoat the situation - if I think their pet isn't going to survive surgery, I tell them that their pet likely won't survive surgery. Maybe that would get me an F in client communications in vet school, but damned if I'm going to say anything that later could be construed as misleading, lying, hiding, evading, etc.
The rest is just minor details and medical records.
