May I recomend:
1. If you are looking for a quick online reference that is free, try the CDEM site from SAEM. It has an outline for approaches to different common complaints and lists a life threat ddx and workup. Then there are pages for individual diagnoses. Decent amount of info, but bite sized, and not overwhelming at all. Here is the site:
http://cdemcurriculum.com/m4/
2. Learn to get out of the room in 10 min or less. Period. You have to learn how to take succinct yet pertinant history/physicals. If the patient is there for abdominal pain, people will care if you asked a past surgical history, but don't care if they have a family history of DM. If the patient is there for URI symptoms, their PSH of an appendectomy 20 years ago probably isn't important.
3. Just like in #2, learn to pare down your presentations to essential details. You have a minute or less to get your point accross before the attending stops listening. We don't want an entire H+P presentation, just pertinant positives/negatives.
4. Always have your own ddx and plan and state them, even if you are unsure. Anyone can go in the room and take a history, scribes are trained to do this with no medical background whatsoever. We need to see that you can assimilate that information and come up with some sort of plan. Don't afraid to be wrong.
5. Check on your labs/studies. If an attending has 15 active patients and you have 2, there should be no way that attending is seeing results before you are.
6. Most students are pretty good at checking for results, but abysmal at rechecking the patient. This will absolutely make you standout. If you pick up on one patient that is getting worse during your month because you were diligent and checked on them, you will look like a superstar.
7. Listen to the rules. If a place tells you to do something a certain way because "thats how we do it here", do it how they want you to. Noone wants to match someone who can't play by the rules.
8. Keep your schedule requests low if possible. I know this is tough in interview season. But the chief residents who make the student schedules also will have some say when it comes to the match. Don't make their life miserable by constantly trying to change things or have unreasonable number of requests.
9. Be nice... to everyone. But don't come across as fake. We've had students carrying and emptying bedpans and trying to do all kinds of scut in order to impress us. Stuff they weren't asked to do and that has no relevance to what they are applying to do (being an EM doc). So treat everyone nicely and with respect, but don't start mopping the floor in order to try and impress someone.
I hope that helps. That's all off the top of my head. I'm sure there's more advice in there somewhere, if I think of anything, I'll be sure to add it!