Normally you are asked to present on a project that you have worked on previously. The presentation is usually quite short, about 10 minutes with 20 minutes for questions and answers afterwards. Most candidates prepare too much material. Focus on your key messages, know your material inside-out, understand your contribution to the effort (what did YOU do, as opposed to what the team did) and think about the lessons you learned and what you would do differently if you had to do it over again.
