I worked for a company as a customer service representative for two years ande have a little sales experience. My advice to anyone who has to do a sales presentation is to just BE YOURSELF! Don't be something you're not! Be friendly, knowledgable, courteous, gracious, presentable in appearance (modest and comely), but don't sell yourself over the product! Prepare ahead of time and know your stuff, have it organized and well displayed, and have everything set up beforehand. Pick something that will be an attention grabber to begin your presentation, have visuals, and make your words count. It's very important to maintain good eye contact during the presentation, but don't stare someone down!
Excellent points, #3. I would add several others in this vein. First, be yourself. You need to be comfortable enough with what you're doing and saying that you can be as relaxed and natural as possible. Your goal should be to sound extemporaneous--conversational in style and tone. Second, keep it simple, stupid (no offense, of course!). Really, keep those ideas as simple as you're able, given the material you need to present. Finally, BE ORGANIZED. Really, it's the most annoying thing to sit through a presentation of any kind (sermon, lecture, whatever) when the points aren't parallel in form, the order is not logical, or there's just too much convolution to follow easily. I lose all respect and interest in such a messy presentation.
Humor is helpful, as already mentioned, as are things like alliteration and acronyms to help the audience remember at least your key points. Eye contact, a positive presence, and an outfit that's not distracting add the finishing touches to any presentation. Good luck!
Just a couple of ideas I think are useful for any kind of presentation. First of all, don't be afraid to use humor in your presentation. But know your audience. If you are not sure your audience will find something funny, then assume they won't and don't use it. Keep your main points short and to the point. You don't want to drown your audience in minute facts that they will never remember and therefore probably won't care about. Also, give them something they can take home with them. Your audience will then feel that at least they got something out of it. You want to give your audience ideas that they can use right away in their jobs. Finally, have fun. If you don't seem to be enjoying the presentation, then your audience probably will not enjoy it.
This is a little hard to answer without any more information about what you are selling or what kind of ideas you need. Are you in search of motivational topics or topics on sales in general?