One of the biggest (and most common) mistakes that presenters make is writing out their entire presentation word-for-word. Most of us learn this technique in Middle School or High School. Our teacher asks us to write a report or paper. Then, later, we might be asked to present that paper to the class in an oral report. Of course, the student will nervously read through the presentation. The teachers believe that allowing the student to read the paper will be easier than just telling the class the content. In reality, though, reading a presentation is much more challenging.
First of all, when people read a presentation, it will often sound very, very, very boring. Think about the State of the Union Speeches that you have seen in the past. I'd wager that most of you have never actually watched or listened to an entire State of the Union Speech from start to finish. Why? Because they are often incredibly boring. Another mistake that presenters make when the realize that they can't just go in and read their whole speech is to try to memorize the entire written speech. This one decision causes more presentation fear than any other. For some reason, we think that if we memorize the speech, we will sound better. That doesn't even make sense. You are saying the same thing, the same way, that you would have if you had the text in front of you. The difference is, though, that if you ever lose your place, your nervousness will increase exponentially.
We write out our presentation to reduce nervousness. However, this presentation habit will likely cause public speaking fear. A better way to design your speech is by identifying just the "most important" items that your audience wants or needs to know. Then, create an outline of these items. You can find a thorough description of how to do this in the post How to Design Presentations Quickly.