Presentations should follow the general outline of introduction, methods, results and discussion. You should not, however, try to present everything you found. You can do that in the paper. For a five minute oral presentation, don't count on your audience remembering more than one or two clear messages from your talk. Thus, choose a few main conclusions to focus on and make sure that the audience gets those one or two points VERY clearly. This means that throughout the talk, you want to focus the audience's attention on the few points you want to make. Let them know from the outset what those points are, explain how the methods allow you to get at those points, describe the results that are relevant to those points, and finish with a clear statement of your conclusions (don't trail off in a wandering microanalysis). At the end of your talk, your audience should know what your main points were, and they should be able to judge for themselves if they think that your experiment proved them.
A common mistake is to go through the paper and read off all the details of the methods. Instead you should focus on the essence of the methods; let them know the basic experimental design. You don't need to list every factor that you controlled for. If people are curious, they will ask whether you controlled for specific things. If you try to tell them everything, they won't remember it all, and they'll miss the main point. Let them ask you for the details, then you'll look really bright and prepared when you can say "we controlled for that", and explain your control at that time.
You should make a few overhead transparencies to help the audience. Clearly, you will want an overhead for any important graph or table. It is also useful to have an overhead stating the hypothesis and another summarizing the main conclusions. I will provide transparency paper. You can draw directly on the transparency, or print or photocopy a figure onto it (by placing the transparency into the manual feed slot of the printer or copier).