I am just a student, but have given lots of lectures to med students, resident, and attendings as I always seek out an opportunity to do so. Regardless, I have several little rules and approaches to presenting, whether it be presenting a research article and explaining how it fits in with current practice, to more informal discussions talking about a case. Lectures tend to be a bit boring and your audience will decide how much they want to pay attention from the first couple of minutes, I always re-read through my slides, and practice them a bit, nothing is worse than having a slide that has too much information, or going through slides too quickly, where the audience thinks you may just try to rush things. I always try to include a high level of "entertainment" as possible to make the presentation interesting, and to take moments to stop and review a little bit, or even to explain information on a slide in two or three different ways, and sort of give a running commentary. The best presentations have emotional content i.e. funny or made you wake up, teach you something new, and spur discussion after the presentation. Like a magician I try to "turn" my audience midway through the presentation, by presenting something new or counter-intuitive, and I try to include new information that I think some attendings don't even know. But, in terms of clothing here is who I would use clothing during the presentation:
1. You could wear a very conservative business suit, starched white shirt, mono-chrome conservative tie, this makes your audience sit up straight a little when you walk in the room, you say, "I am going to present a topic that is little understood in clinical medicine today . . . " something to make it a story, instead of let's look at 35 slides and go over dosages of all possible drug combinations of how to treat meningitis, ok . . . Then you make a joke, everybody laughs because it comes from someone who is acting very conservatively, and you have the audience hooked, why is this guy who started so serious making jokes, what is he saying? Or you could lighten up the topic by mid-way through stepping away from the podium, say you want to talk about an interesting case that you had, what people really get is a little intermission where they can listen to you talk, a live person, you can even make it interactive by asking harmless easy to answer questions. It is always useful to put stuff in perspective too, i.e. this treatment may be coming to our ICU soon. Always have alot of energy at the begining of the talk as this energy is transmitted to your audience if they think you aren't excited to give the talk they won't be excited either. I would avoid pictures of your family and home because it gives the audience a sense that you would rather be with them, and they start thinking about time with their families. Give the audience brownie points in the begining i.e. the first 3-4 slides should cover information they know by heart, it makes them feel smart and more able to tackle all of the other information, and make comments with easy slides saying as we all know. . . this builds a comraderie with your audience i.e. if a cardiac surgeon says, "as we are all acutelly aware, the impact of hypertension on cardiovascular health is quite substantial, when patients come to me for a CABG . . . " as opposed to, "our group of cardiac surgeons is investigating a new technique which you are probably not aware" This makes everyone feel part of the team, and for one hour they think like a cardiac surgeon, neonatologist, etc . . .
2. I would advise against wearing a white lab coat because it looks to sterile, it looks like you need to feel like a big powerful doctor and wear you white lab coat everywhere, or that you are rushed and need to be back in the clinic.
3. Casual attire, i.e. shirt, with tie, not TOO distracting people shouldn't be looking at your mickey mouse tie during the talk and this be the only thing that they remember. I would always wear a boring tie (not a bowtie) as if you are too flashy you will alientate some of the audience, and never wear a funny tie if you plan on doing some jokes. The benefit of casual attire is that it makes the whole show more relaxing, if you dress without a suit, then don't just recite what is one the slides, but be the guy who had the informercials who tried to sell Juice-A-Mattic, make hand gestures and sell your information to the audience, i.e. if there was one thing I wished you would learn from this talk it would be that in the special case when you have a patient or here is something I wished I knew about earlier. If you do dress casual be prepared to work the audience, i.e. as above taking time to go into the audience a talk for 4-5 minutes. I would recommend wearing a solid blue starched shirt that is freshly ironed, a conservative tie.
I also use graphic heavy i.e. special slide animation in powerpoints, very picture heavy, very diagram heavy. Best background IMHO is purple or dark blue with light yellow font, best contrast, easier to read. My strategies work one student told me that my presentation was the "best ever" compared to all her lectures in medical school and they she was surprised that she stayed awake and actually learned something. Out of probably 12 presentations done to date, 10 the attending said it was "very good" or "good" or "excellent" and students always said that that was "very good" and asked me follow-up questions on the way out, usually I get a good discussion going at the end, and people say "huh" that is interesting, the ones that I only got a couple good comments were the ones I only had like 2 days to prepare, I usually spend 1 to 2 hours each night for a week working on said presentations, practice does help and be sure to edit your slides at least twice! But remember, always at the begining tell them how excited and happy you to tell them about the juice-a-matic or what have you