Building a personal brand is not about ego or vanity, one expert explains.

FORTUNE -- Dear Annie: I read your recent column on being too shy to speak up at work with interest, because my situation is kind of similar. I work for someone who keeps bringing up my ideas in meetings with senior management before I get the chance to speak; and he talks about these solutions I've come up with as if they were his own, with no mention of me at all.

A friend who has witnessed this tells me I need to "promote my personal brand" so that people in the company and elsewhere know that I've become something of an expert in my area, which is streamlining processes and improving operational efficiency. But it's really hard for me to blow my own horn and brag about what I've done. Isn't there some other, more subtle way of letting higher-ups know what I've contributed (without seeming to criticize my boss for swiping the credit), or should I just let it go? -- Unsung Hero

Dear Unsung: Your friend is giving you smart advice. But before you can follow it, you need to understand exactly what a personal brand is. Contrary to a widespread misconception, branding and bragging are not at all the same thing.

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"Often, people hear words like 'self-promotion' and 'marketing yourself,' and they just cringe, because they think it's about boasting, and they don't want to do that," observes Karen Kang. "But creating a personal brand is really a process of education. It's about sharing information and participating in discussions about ideas. The goal is to make decision-makers aware of what skills you have and what value you can add."

A former partner in Silicon Valley marketing powerhouse Regis McKenna (the branding brains behind Apple (AAPL) and Intel (INTC), among others) Kang now runs her own Palo Alto-based firm, BrandingPays, and has coached executives at companies like AT&T (T), HP (HPQ),and NCR on how to become known for their expertise. She also wrote a book, Branding Pays: A Five-Step System to Reinvent Your Personal Brand.

Once upon a time, in the pre-Internet economy, polishing your very own brand was not really necessary. After all, if you were going to spend your whole career climbing the ladder at one company, or two or three at the most, everyone who mattered already knew firsthand what you were good at. But now that job security is a discarded relic, and most people change companies (or even careers) eight or 10 times before hanging up their spurs, it's a much different world. Each of us is probably the only one keeping track of our achievements along the way.

"We're all free agents now," says Kang. "And that doesn't work unless people make the effort to brand themselves. Anyone who's trying to launch a project, put a new team together, or reach any particular goal needs to know who's out there with the required skills and what expertise is available."

So what does that imply for your current situation? Instead of trying to let senior managers at your current company know that certain specific ideas were really yours, think bigger and longer-term, Kang says. A good place to start is with your LinkedIn profile. "Make sure it's up to date, and contains key words that people might look for," she advises. "Mention your expertise in the headline, instead of burying it farther down on the page." Use strategic terms (for example, "streamlining processes") rather than tactical ones (e.g., "cost-cutting").

Kang adds, "People often go to LinkedIn when they're looking for fresh talent, either external or internal, so you want your profile to clearly state what you have to offer." She also recommends volunteering for cross-functional projects, "so you can demonstrate your knowledge to people outside your own department, and speak up in meetings where your boss isn't."

The Internet provides a slew of ways besides LinkedIn to get your brand across to vast numbers of people in your company and industry. For instance, "contribute articles to industry websites and publications, or follow the influential blogs in your field and make thoughtful, informative comments that showcase what you know," Kang suggests. "Then you can link to these on Facebook or your company intranet, and tweet the link to your followers -- not to say, 'Look at this cool thing I wrote!' but rather, 'Here are some insights about XYZ that might interest you.'"

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Another digital brand booster: "Consider having your own website, called simply Yourname.com, where you can put up work product or share your thoughts and analyses of different aspects of your field," Kang suggests. "You can link to it from your LinkedIn profile, to give people a more detailed look at who you are and what you can do."

Once you've begun to build a widespread reputation, you're likely to find new opportunities coming your way that transcend the reach of your limelight-stealing boss. "It's really your obligation to share what you know, so that the people who need you can find you," says Kang. "When I work with clients who initially think that branding is about bragging, there's always an 'aha moment' when they see that it's really about engaging with the world."

Talkback: If you've created a personal brand that has furthered your career, what has worked best for you? Leave a comment below.