Think about all the extremely successful people you know. I guarantee they're incredibly good at selling themselves, selling their ideas--in short, they're incredibly good at persuading other people.
But being persuasive doesn't mean you have to manipulate or pressure other people.

1. Start by gaining small "wins."
Research shows--yep, more research--that gaining agreement has an enduring effect, even if only over the short term.
So instead of jumping right to the end of your argument, start with statements or premises you know your audience will agree with. Build a foundation for further agreement.

2. Take strong stands.
You would assume data and reasoning always win the day, right? Nope. Research shows humans prefer cockiness to expertise. We naturally assume confidence equates with skill.
Even the most skeptical people tend to be at least partly persuaded by a confident speaker. In fact, we prefer advice from a confident source, even to the point that we will forgive a poor track record.
So be bold. Stop saying, "I think" or "I believe." Stop adding qualifiers to your speech. If you think something will work, say it will work. If you believe something will work, say it will work.

3. Adjust your rate of speech.
There's reason behind the "fast-talking salesman" stereotype: In certain situations, talking fast works. Other times, not so much.
Here's what one study indicates:
  • If your audience is likely to disagree, speak faster.
  • If your audience is likely to agree, speak slower.
Here's why. When your audience is inclined to disagree with you, speaking faster gives them less time to form their own counterarguments, giving you a better chance of persuading them.
When your audience is inclined to agree with you, speaking slowly gives them time to evaluate your arguments and factor in a few of their own thoughts. The combination of your reasoning plus their initial bias means they are more likely to, at least in part, persuade themselves.

4. Don't be afraid to be (appropriately) "unprofessional."
Take swearing. Cursing for no reason is just cursing.
But say your team needs to pull together right freaking now. Tossing in an occasional--and heartfelt--curse word can actually help instill a sense of urgency because it shows you care. (And of course it never hurts when a leader lets a little frustration or anger show, too.)

5. Know how your audience prefers to process information.
A fellow supervisor used to frustrate the crap out of me. (See? That swearing thing works.)
I was young and enthusiastic and would burst into his office with an awesome idea, lay out all my facts and figures, wait breathlessly for him to agree with me...and he would disagree.
Every. Freaking. Time.
After a number of failed attempts, I finally realized he wasn't the problem. Myapproach was the problem. He needed time to think. He needed time to process. By demanding an immediate answer, I put him on the defensive. In the absence of time to reflect, he would fall back on the safe choice: staying with the status quo.
So I tried a different approach. "Don," I said, "I have an idea that I think makes sense, but I feel sure there are things I'm missing. If I run it by you, could you think about it for a day or two and then tell me what you think?"
He loved that approach. One, it showed I valued his wisdom and experience. Two, it showed I didn't just want him to agree--I genuinely wanted his opinion. And most important, it gave him time to process my idea the way he felt most comfortable.

6. Share the good and the bad.
According to University of Illinois professor Daniel O'Keefe, sharing an opposing viewpoint or two is more persuasive than sticking solely to your argument.
Why? Very few ideas or proposals are perfect. Your audience knows that. They know there are other perspectives and potential outcomes.
So meet them head on. Talk about the things they're already considering. Discuss potential negatives and show how you will mitigate or overcome those problems.

7. Focus on drawing positive conclusions. 
Which of the following statements is more persuasive?
  • "Stop making so many mistakes," or
  • "Be much more accurate."
Or these two?
  • "Stop feeling so lethargic," or
  • "Feel a lot more energetic."
While it's tempting to use scare tactics, positive outcome statements tend to be more persuasive. (The researchers hypothesized that most people respond negatively to feeling bullied or guilted into changing a behavior.)
So if you're trying to produce change, focus on the positives of that change. Take your audience to a better place instead of telling your audience what to avoid.

8. Choose the right medium.
Say you're a man hoping to convince a man you don't know well, or even at all. What should you do? If you have a choice, don't speak in person. Write an email first.
As a general rule, men tend to feel competitive in person and turn what should be a conversation into a contest we think we need to win. (Be honest; you know you do it sometimes.)
The opposite is true if you're a woman hoping to persuade other women. According to the researchers, women are "more focused on relationships," so in-person communication tends to be more effective.

9. Most of all, make sure you're right.
Persuasive people understand how to frame and deliver their messages, but most importantly, they embrace the fact that the message is what matters most.
So be clear, be concise, be to the point, and win the day because your data, reasoning, and conclusions are beyond reproach.
And always use your persuasion skills for good, not evil. The art of persuasion should be the icing on an undeniably logical cake.
Thank you to Jeff Haden for formulating this article on behalf of inc.com