Practice your presentation for friends, in front of the mirror, or on videotape.
Familiarize yourself with the environment of the room in which you will speak (size of the room, quality of microphone, podium, height of the lectern, etc.).
Make sure all the equipment works and that you know how to use it (VCR, projector, microphone, etc.).
Make sure your visual aids are clear. The content of visual aids should support your points, not confuse the audience. If your visual aid presents several columns of data, use a piece of paper to cover the columns you have yet to discuss. Use large type on all visual aids.
Be relaxed, but maintain good posture. Stand up straight and hold your head up straight. Breathe quietly and deeply.
Use your voice for projection and inflection. Don't forget the importance of pauses. Don't be afraid of silence. Silence can be extremely effective and is certainly preferable to filler words such as "uh," "you know," and "like."
Use your hands sparingly. Too much use of the hands and repetitive motions are distractive.
Maintain eye contact with both sides of the room. Whether you are reading, speaking from notes, or talking extemporaneously, it is important to look at your audience. If it is difficult for you to look directly at people, then look at their foreheads or just above their heads.
Adjust the microphone to the proper position before you begin to speak. Be conscious of where the microphone is, but do not lean into the microphone.
Speak slowly and clearly. Most people have a tendency to speak too fast when speaking in public.
Do not go over your time limit. Practicing your presentation should eliminate this problem. If, however, the "question and answer" session extends beyond the time limit, it is your responsibility to end the discussion as quickly as possible.