First of all, not knowing what in fact the aim of your presentation is should be a clear warning sign for you. If the sense or purpose is not obvious, then you need to clarify this issue immediately. Otherwise, there is no point in proceeding any further.
Have you prepared a script for the presentation?
Maybe a script will give you more confidence. But be careful: having everything written down in advance is not advisable and may even be playing with fire. The problem is that if you need a script to recite, you probably don’t know enough about your subject matter. The website presentationblogger.com specifically discourages using a script. Instead, just prepare a rough outline of the main topics you want to talk about.
Maybe you think memorising the first three sentences will work for you. Then, however, having delivered the initial words, you get deeper into your talk and suddenly know nothing. Don’t memorise lines: this suggests you are striving for perfection, which is unachievable anyway. It is far better to prepare yourself by fully understanding your subject matter.
Of course, it is good to think through what you are going to say, but spare your audience a monotonous recital. Forget about the script and just start talking about your subject. Stay genuine and authentic.
Don’t use slides as cue cards
This is a mistake which could become the source of huge embarrassment. It can easily happen that you will be standing there most of the time with your back to the audience while you try to figure out what you wanted to say regarding the key words on your slide. Such a presentation will be boring and not in the least engaging.
If there are cue cards on the screen, people will probably end up looking out of the window rather than listen to you.
-jk-