Be prepared. The overall process can be intimidating depending on the position you are trying to reach. It is not that bad once you get going. Some people only do the interview via skype at this point. However, if you have to do a presentation be aware that the room will be crowded and there will be people from many different areas of outreach. In fact, you may never see those people again in the time you work there. As long as you do your research beforehand, you should be fine.