Successful speaking is about power used benevolently. Good speakers don't need to manipulate audiences. At the same time, they realize that they must exert control at every turn: over the material, the passage of time, an audience's response, and over their own body. 

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The nature of the audience, the speaking situation, your purpose . . . even the emotional context of an event matter greatly. Yet you must  also control that most critical of public speaking components: your body language. Here are The Body Language Rules: 12 powerful ways you can use nonverbal communication to make you a more credible and dynamic speaker in the minds of your audience:

1. Always Stand if You Can. Your body is such an important communication tool that it's a shame to deprive your audience of 50% of it. Yet that's what happens when you sit down to make a presentation (where you have a choice). Your position in a room and full-body movements are part of your power. Give your audience all of you. And know the 5 body language errors that will sink your presentation.
2. Ground Yourself. "Grounding" means to assume a strong stance, with your feet at armpit-width and your weight evenly distributed. Setting yourself like this gives you the appearance of stability. You will appear steadfast—and your audience will see your ideas that way too.
3. Keep Your Arms in Neutral. Self-consciousness in speaking means you're apt to do everything with your arms except what they're meant to do at the start of a presentation: hang at your sides. That's the "neutral" position; from here, you can bring your arms up to make gestures naturally. Keeping them above the waist at all times only calls attention to them.
4. Use Open Body Positions. Crossing your arms or locking your hands in any way creates a barrier between you and your listeners. Instead, keep your upper body open, so there's literally nothing between you and the audience. Influence and rapport will flow freely in both directions. An open stance is also part of the body language self-image you're broadcasting.
5. If You're Sitting, Sit Straight and Slightly Forward. Let's say you have to sit to deliver your talk, as some situations require. Bring your backside one-third of the way forward on the seat, and lean in slightly. You'll look professional, engaged, and interested. Lean back or slouch and you'll be comfortable but much less effective.
6. Make Your Gestures Spare and Clean. Don't worry about using your hands too much—just use them effectively. Gestures used only where you really want to emphasize something will do just that. If you make each gesture strong and "clean" in the sense of well defined, it will possess its own power.
7. Move with Purpose. Some speakers wander like a cloud; others pace annoyingly. For your part, move with purpose. Take a couple of steps just before you start a new talking point. Approach a questioner; or go to the screen to point out something. Visuals like this help an audience's interest and retention of what you're saying. On the other hand, inappropriate body language can destroy your own message.
8. Love Your Audience More than Your Manuscript. Speeches aren't occasions for audiences to be read to. They are performances where you share what you know with people interested in hearing it. The exact words you say don't matter in the least; opening up a communication channel does. Look at the people you want to influence. Glance down for the next talking point, but no more.
9. Love Your Audience More than the PowerPoint Screen. Why? Well, the screen won't love you back for one thing. Pay more attention to those you're trying to persuade than to the data that helps you do so. If you have to look at the screen to remind you of what comes next, you're not ready to take this act on the road.
10. Move Away from the Podium . . . and Keep Your Hands Where I Can See Them. All right, I'm having fun here. But the podium or lectern is a physical barrier between you and everyone else. Don't hang on it, or even rest both hands there—you need your hands to gesture. Best of all is to step to the side and speak. You can always go back to see your next talking point, then come away again. Here's a humorous look at what happens when you allow a lectern to dominate you.
11. Welcome Questioners. If you're lucky enough to have people question or challenge you, you should make them feel welcome. Avoid pointing a finger aggressively in the questioner's direction; use an open palm gesture instead. It's a subtle yet effective way to keep an audience on your side.
12. Don't Hold a Writing Instrument Unless You're Prepared to Use It. Ever notice how many speakers hold a marker while presenting near a whiteboard or flip chart that they never actually write on? A variation is the speaker who's been taking notes up to the last minute and forgets that the pen is still in his or her hand. The audience waits in vain for the instrument to be used!

The language of nonverbal communication is often as important as the verbal content of your speech or presentation. Learn to use it to your advantage. Remember: a body is a terrible thing to waste.

Key takeaways from this blog:

• Body language is one way good speakers control the speaking environment.
• Stand if you have the choice, so you can use full-body communication.
• Start with arms in the neutral position, and make your gestures clean and spare.
• Move with purpose, and don't get stuck behind the podium.
• Look at your audience more than anyplace else to be able to influence them.