ALiEM has a great summary of what an EM presentation should sound like — a must watch for an M3 or M4 rotator:
The 3-minute EM Student Presentation
The International Emergency Medicine Education Project has recently compiled an incredibly thorough clerkship guide and have made it free and available as a PDF or iBook. Don’t expect to read it cover to cover, but perhaps utilize it as a reference for topics that you may be struggling through. This resource was compiled by an international cohort of EM physicians, so take note that there may be subtle practice variations from what you see in the US.