There are some people who would sooner do anything to avoid standing up in front of a crowd. If you are in sales, or management then the chances that you will be called upon to give some kind of presentation are pretty high. To add further stress it is likely that it will be infrequent enough that you will have forgotten all the lessons that you learned last time you gave a presentation!
So ... what can you do?
The generalist answer is preparation and practice, which means knowing your topic well and either practicing this particular speech enough to ensure you can deliver with confidence or finding other ways to practice regularly.
OK ... now you know everything you need to know, right? General advice is "generally" pretty useless. It is the kind of advice we get from the people who are quick to criticise us when we fall flat on our faces. So here is some practical advice that should help ...
Preparation. There is a fine balance here. You likely can't spend days and days putting the material together, but you need to do enough work to make sure you are comfortable with the material. Use ALL of your resources, gather information and content from anywhere you can get it ... don't try to reinvent the wheel. Use the 80/20 rule to ensure that you are not spending 80% of your effort on the final 20% of content!
Organization. It is important thing to organize your thoughts in a logical manner and in a way that your audience will grasp. An introduction that tells them what you are going to "tell them". The body of the presentation with the detail about your major points; and a wrap-up that tells them what you told them.
Detail. It is easy to bore people, so keep to the highlights ... smaller items could be addressed in a question and answer session. Presentation slides should not be busy and only a few l=key points on each slide.
Timing. Work out the timing for your presentation and make sure you hit it! If you have an hour for presentation and questions then you should ensure there is time left for questions. You should also ensure that your talk is not done in 15 minutes!
Audience engagement. You need to understand your audience and aim the content at them. If its a very senior audience then getting into technical detail will "kill them", if its a very technical audience then flying at 30,000 feet might just be too superficial for them.
Technology. If you use PowerPoint for your presentation then there are some great words of advice in this article ... six fabulous presentation tips for IT professionals.
Once you have your presentation then practice it ... in front of a mirror, or a friend, or your colleagues if that makes sense. Get feedback and then practice until you are very comfortable with the material.
Having done all of the above you will be well prepared, and that should provide a level of confidence that things will go OK. On the day you will get some jitters, everybody does, just remember to breath deeply, talk at a slightly slower pace than your normal conversation and act confident (yeah I know ... just fake it).
Having said all of this ... the bast advice I can give to anyone who might be called upon to give presentations is to join Toastmasters, which I did write about in May 2007. This way you can get regular practice, and good advice while you hone your skills. Like everything, it is learning and practice that makes you better at giving presentations.