A bioscientist recently complained about a talk she had attended given by the head of research of a large biopharmaceutical company. The speaker had a stellar international reputation, and the audience keenly anticipated his keynote address. My friend was frustrated, and she proceeded to explain why. The speaker read from his notes, rarely looked at the audience, and sounded as if he was bored by his own talk. He droned on at great length about the development of a drug, reciting so many details that the relevant ones were lost on the audience.

Why was the talk a failure? First, he didn't discriminate between reading a paper and giving a talk. Second, he didn't target the presentation to the audience, most of whom knew nothing about the drug or the methodology. He ignored the fact that his entire body was participating in the presentation. Finally, he forgot that audiences crave personal contact with speakers, especially eye contact. Otherwise, why not simply go to the library and read the speaker's papers?

You can avoid these mistakes and significantly improve your presentations by practicing some simple rules. First, recognize essential differences between publishing research articles and speaking in front of an audience. Whenever you write or speak about your work, you must both inform and persuade, and you must decide how to balance these activities. In a talk, however, you are also a performer, and some of the rules of the theater apply. You have the opportunity to be especially persuasive - audiences are generally more open to being persuaded by a speaker than by a writer. In addition, unlike a paper, a presentation will be received only once. It must therefore be simpler, and visuals must be used more directly to enhance it.

The first step toward giving a good presentation is to determine why you are speaking and what you want to achieve. Why give the talk at all? Apart from communicating the information you want to provide, how will it help your career or other objectives? Carefully consider who your audience will be and what they are likely to know about the subject. Next, choose one central point that you want to get across and write it down. Everything in your talk should relate to that point. If you write an outline for the talk - which I highly recommend - check it carefully to make sure that every point is related to the theme.

When you begin to prepare your outline or notes, it is helpful to write down a list of questions that your audience might want answered. Rather than trying to replicate the standard journal format, consider using answers to four or five questions as segments of your talk. No matter which structure you use, the introduction should foreshadow the entire talk, and the conclusion should summarize your major points and how you arrived at them.

When you outline, and later when you rehearse your talk, pay special attention to how you make transitions between different sections. When working with clients, I have found that speakers frequently fail to make their transitions explicit because the logic of the talk is far more obvious to them than to their listeners. Using visual aids wisely will help listeners follow the flow of your talk. In fact, some speakers create their visuals first and build their talks around them.

Although planning the content of the talk is essential, inexperienced speakers also need to repeatedly practice their delivery. You could practice with a tape recorder or with a friend, or join an organization of people who will help you to rehearse. Whatever you do, use a stopwatch. Don't be surprised if you speak too quickly and yet still exceed your allotted time. Remember that you don't need to present everything you know; in fact, information overload will only confuse the audience. Often, people will pay closer attention to presenters who speak slowly; this gives the audience time to process every word rather than having to struggle to keep up.

Using a tape recorder is the simplest but perhaps the most intimidating way to rehearse. Without the empathy and encouragement of other people, it is easy to be unnecessarily critical of yourself. However, some people use the tape recorder very effectively. If you use a recorder, tape your rehearsals five or six times and note your improvement. You might find it easier to rehearse in front of a sympathetic friend, colleague, or advisor. Also, consider giving your talk at an in-house seminar before venturing into a conference. Your seminar colleagues should be sympathetic while providing constructive criticism. Finally, consider joining a group such as Toastmasters International, a nonprofit organization with branches in many major cities that helps people improve their public speaking. For a small membership fee and annual dues, you can learn how to give preplanned lectures and impromptu talks, by both giving presentations and offering supportive critiques of the presentations of other members. I know people who rave about how this organization has improved their speaking abilities.

When you rehearse, let your jaw relax, and open your mouth more than usual. This will help relax your throat and enable you to project your voice. Also, pay close attention to your breathing. As a separate exercise, place your hands near your navel and practice breathing into your belly. You should feel your abdomen rise and fall with your breath. This type of diaphragmatic breathing will relax you, deepen and slow your breath, and give you more energy for your delivery. During your presentation, you can put your hand on your belly briefly if you begin to feel anxious. This action can move you back into the diaphragmatic breathing and quickly relax you.

When you practice, get as much visual feedback as possible - from a simple mirror, a discerning observer, or even a videotape. How and where you stand and how (and when) you use gestures are important for effectively addressing a scientific audience.

In the weeks before your talk, study the good and bad habits of different types of speakers, and note what makes them effective or ineffective. In addition, you may find it helpful to listen to or watch politicians and polished journalists. Listen to the cadence, as well as the tone, pitch, and volume of speech. To become more aware of body language, try watching polished speakers on television after turning down the volume.

You can improve your presentation for almost any public talk by making a few simple preparations before you speak. If you haven't done so before, examine the list of speakers and topics at the meeting to help you to better understand your audience's expectations. Check the room where you will be presenting. Walk around it, sit in it for a few minutes, and get comfortable with the space. If possible, carefully test the microphone and any audiovisual equipment that the conference will supply. This step can avoid the headache of a screeching microphone or sudden loss of visuals during your talk.

It is a good idea to exercise vigorously or practice relaxation techniques on the day of your talk. Professional speakers eat very lightly or not at all before talks to avoid sluggishness or stomach problems (or embarrassing noises from the podium!). An empty stomach also deepens your breathing, which will relax and energize you during the talk.

I recommend that you also warm up your voice. Whether you sing in the shower or practice do-re-mi ten minutes before your talk, such warm-ups will calm you and open up your throat for a better sound. Drinking water during the talk will always help your throat, and it is a good excuse for pausing if you become anxious. If the organizers don't set you up with water at the podium, be sure to arrange it.

Before you take the podium, you might remind yourself that stage fright is a natural condition and that it may disappear once you are involved with your presentation. If you accept the reality that you are nervous about public speaking, you can avoid feeding an anxiety cycle, where you feel anxiety about being anxious.

As soon as you are introduced, step up to the podium, pause to take a deep breath while you notice the crowd's eagerness to hear your thoughts, glance at your notes, and remember how well you have prepared. You're ready to dazzle them!