One of the most obvious and common problems encountered when making public presentations has to do with organization. Each individual is different and 16 or more individuals serve to makeup a typical audience. That puts a burden on the speaker immediately. The fit of the topic, speaker and audience is critical to success. How the ideas are organized merits a great deal of attention. The temptation is to spend most of the time gathering and the data and preparation of notes and presentation materials.
The data is important. But the fit of the data to the audience and the speaker is critical. How should the data be characterized? Why should the audience care about what they are hearing? What should they do with the data they are hearing? Which items are critical to audience understanding? What do they need to know in general before they will understand what the speaker is saying? What does the audience need to know first and last? How are they going to recall what is being said to them? These are organizational considerations. They are almost always given little or no attention.
First, know what your goal is? Surround and review the data that is the essence of what is going to be said and fit it to the audience. Then ask if this audience needs to be able to listen to what you have to say? Careful planning (organization) will enable the speaker to talk to an audience commanding their attention, aiding them to understand and follow what is being said and then recall it when the time comes to use the information.
Of course this entire process fits communication no matter how large the audience is.