Before to do a presentation, I think that it's very important to analyze the audience you are going to speak to.
There are several techniques to speak in public, for example speakers can use metaphors, jokes, comparisons, or just they can go directly to the point.
The corporal expression and the personal presentation are very important. Personal experiences are valuable to show your own work and to express your points of view to the audience.
Throughout images you can capture the audiences' attention. The use of text could be a bad idea; the audience could be bored.They wont read.
It is important to have a kind of a conversation with the audience. If you seem relax and have the correct arguments to talk about a subject the audience could understand the main idea of your presentation.