I would agree with the posts above. I taught speech for over 10 years to HS students and have used the following pointers for those who suffer "stage fright".
1. Prepare thoroughly. You don't have to memorize your speech completely but know your subject well enough so that you feel that you are having a conversation with a group of friends and/or acquaintance.
2. Jot down your main points on a 3x5 card or cards (if you use more than one be sure to number them in case they fall to the ground...
) Use them to assist you but avoid, whenever possible, reading from them (see #1 above).
3. Practice your presentation at least 2-3 time beforehand in front of a small audience (if possible). This will allow you to go through your notes (both mental and physical) work with your AV materials (PowerPoint presentation slides, charts, handouts, etc.) and get a positive critique from people you trust and who won't "flame" you.
4. Once you are in front of your target audience use non-verbal communication to aid you in releasing any "pent-up" energy. Gestures and other body movements (moving around the room to accentuate a point) if done naturally allow the speaker to look relaxed and comfortable. However, don't use gestures that are jerky, too fast or hide your facial features. These detract from your speech and are noticeable. If you use a podium or lectern don't grasp it as a drowning man grasps a life jacket. The "white knuckle" look is a sure sign of apprehension. If you don't know what to do with your hands don't put them in your pockets place them naturally at your sides and let them hang.
5. Use humor judiciously. Many people begin with an anecdote, a joke or a funny story. If that suits you and you feel comfortable telling a story do so. I would caution against off-color or "blue" material especially if it is to a group that you don't really know, or that you are trying to make a good impression (and who isn't). The worst thing you can do is to have a joke fall flat and get off on the wrong foot. My best advice is to save the jokes for the professional comedians and if you must make the story something that everyone can empathize with. or is personal to you and illustrates a point you are trying to make.
6. Maintain adequate eye contact but don't "bore a hole" in someone's forehead. Glance naturally around the room picking out one or two people in different segments of the audience. Appropriate audience behavior is for them to look back at you. If this is disquieting simply break the gaze and move on. Make it look like you are simply making conversation and not searching for a long-lost friend at a crowded bus station and everyone will feel comfortable with your eye contact.
7. Speak loud enough to cover the room but don't shout or whisper unless for dramatic effect. People who are hard of hearing will be seen straining forward to hear you. If you notice this speak up. Conversely if the sound of your voice fills the room then you may need to turn the modulation down slightly to keep those in the front row from becoming numbed or intimidated.
8. Enjoy the experience. I have heard that public speaking is the second greatest fear behind death. I don't believe it. I have observed thousands of speeches from hundreds and hundreds of students and adults. None have ever died and none have ever even fainted! Public speaking is what you make it. If you believe you'll be cool, calm and comfortable you probably will be. If you look at the lectern like a man looks at a guillotine right before his final haircut then your experience will probably end up as a bloody mess!