I worked for a very large company for many years and it got to the point that you couldn't make a cuppa without giving a 15 minute Powerpoint Presentation on why, when, how etc!
Large companies, or at least the Management of such companies are obsessed with presentations. I suppose it lets them feel important and maybe a little informed.
I have delivered and sat in on loads and I have come to the opinion that the vast majority are a complete waste of time. I doubt if anyone remembers any part of a presentation a couple of months on; unless of course it is a disaster, then it will be remembered, or at least the presenter will for all eternity:-)
OK, so none of the above is that helpful so a few tips: -
Use Powerpoint (it will make things so much easier)
Stick to bullet points on the actual slides then talk in more detail about each (always be concise, don't waffle).
Know your subject. Keep a logical progression / structure.
Make sure that your presentation has just one theme or message to be conveyed.
Be entertaining and don't overdo statistics or figures. The lighter presentations are usually the best received. If possible use props and involve a couple of people from the audience.
15 minutes will fly by. The difficulty will be staying within your time.
Definitely practice and time yourself (deliver it to friends and family; this will prove more difficult than to strangers as the embarrassment levels will be way higher). After a couple of trial runs you will be surprised just how easy it is to get through this.
Everyone gets nervous. I always do. I know people who do this for a living and most of these still get nervous before each presentation. This isn't a bad thing. As long as you know your subject and have prepared yourself properly then it will be over before you know it and you'l have a happy audience.
Best of luck
Ian