It is a wise thing to plan what you will be saying and doing before your presentation starts. Even more important be cognizant of what is going on in the customers’ mind during the presentation. You want to make the prospect want to own what you are presenting. During the presentation keep these things in mind and be aware of them.

Try to find out what their needs are:

You must find out the hot button, the most important motive that would cause the prospect to buy. Is it convenience, pride of ownership, accuracy etc.?
What is the prospects biggest headache or his greatest weakness in what he is doing now?
How is he doing what he is doing now?

Explain Benefits
Here you show clearly how each of the major benefits applies to his business. How will what you are presenting benefit him, help him obtain more profits, provide greater convenience, perhaps more or better information.

Proof- Offer it.
Are your claims backed up by evidence? Does what you are demonstrating fit his needs? You can use testimonials, user lists, literature, portfolios.
Is there anyone near that the prospect can call or visit to support your claims? ( Careful here, before you do this make sure the person you recommend is on your side and will support, not hinder you.)
Can you compare the present way things are being done to what you are presenting. Emphasize the benefits of using what you are presenting and prove it? Try the split T method, Column A what is being done now. Column B how it will be improved.

Close-Ask for the order
A gentleman who was old, wise and monumentally successful when I was just starting out would say one thing to me while I passed his desk on the way out of the office “Do not forget to ask for the order”. Did you get agreement on several points or on the main point – did you hit the hot buttons?
Did you answer all questions and handle all objections that were raised?
A good way to close is to sum up each of the agreed upon points and ask for the order.

Trying to envision these things before the presentation starts is helpful but keeping them in mind during the presentation is what will give you the best chance for success.

Oh and let me add this,” Do not forget to ask for the order”.