As an entrepreneur or business leader, knowing how to speak to an audience is a necessary job skill. Wouldn't it be nice if it were also a steady source of income? It can be--if you approach it right. That insight comes from Alaina G. Levine, frequent public speaker and founder of Quantum Success Solutions, and a speaking coach.

Just how much money can you make as professional speaker? "I know entrepreneurs who make $5,000 a year speaking, and $300,000 a year speaking and everything in between," she says. "I know people who charge $500 for a speech, or $7,500 for a day, or $20,000 for a keynote at a corporate event."

It all depends on factors such as how experienced you are, how well-known you are in your industry (or beyond), and how much time you're willing to devote to marketing and growing your speaking business. A lot also depends on the audiences you speak for. Non-profit, local groups may have little or nothing to pay. National trade associations or corporations will likely have deeper pockets and will pay a lot more.

The good news is that, as an entrepreneur, you already have many of the skills you need to become a successful speaker, because launching a speaking business is similar to launching a new product or company. If you want to give it a try, here's some advice from Levine.

1. Make it about them, not you.

If you were planning a new product launch, you wouldn't base it on what you felt like selling, but on what your customers wanted to buy. Yet, when it comes to professional speaking, many smart entrepreneurs still make the mistake of basing their plans on what they feel prepared to talk about, not what an audience might need from them.

"It starts with understanding that if you're to be paid to speak, there has to be some sort of transformation that you're providing the audience," Levine says. "You have to solve a problem for them or advance their agenda, whatever that agenda happens to be." One big mistake many entrepreneurs make is to assume that because they have an interesting story to tell or knowledge to share, that someone will pay them to speak, she adds. "You most likely do have something of interest to say, but you have to translate it into a solution for that audience. And that's the work. That's the challenge. What are you uniquely capable to help people with?"

2. Spend time on market research.

Finding the answer to that question will likely require some market research, just as you would do if you were going to offer a new product or service (which is in fact what you are doing). Levine's own professional speaking career began after she heard from potential employers that STEM students from the Masters' program at the University of Arizona where she was program manager, weren't getting hired because they lacked "soft" skills such as communication, networking and leadership. She began teaching these skills to her students, and then realized that many people in STEM professions needed to learn them too. "That is transformation for that audience because it gets them jobs," she says.

Early in her speaking career, she also tried to market herself as a motivational speaker, she says. "That was a mistake. There were a lot of motivational speaker and that was not the core value I could provide." Learning to identify and market her unique value proposition was the first step in building her speaking business as a source of income.

3. Practice.

As with anything else, the more speaking you do, the better you'll be at it. So if you want to become a professional speaker, Levine suggests starting out, as she did, by doing many free engagements. It takes time onstage to learn how to really engage an audience, she explains, and to fine-tune your message and your presentation. "When you're starting out in your speaking business, very rarely will you be paid for those first encounters. It's going to take time to build the platform skills and the reputation to be able to command those fees that are higher. It's also going to take networking." By speaking for free, Levine says, she grew a network of people who had seen her speak and knew the value she offered, which led to paid speaking later on. 

4. Be entrepreneurial.

Levine advises having your email address and phone number on every page of your website, so that an event planner can easily find it. And she recommends answering your phone whenever it rings, otherwise they might move on to someone else.

Beyond that, act like an entrepreneur. Years ago, when she still worked for the University of Arizona, Levine attended a day-long professional development session with a disappointing keynote speaker. "She was awful and she made the audience feel awful," she says. So she called the event manager and said, "That was an interesting workshop. I'd like to submit myself to be the keynote speaker next time." She asked how much he had paid the keynoter and agreed to do it for the same fee. "That was my first paid speaking engagement," she says.