Dear L.U.: You may well ask. The nice part about being new to the site is that you get to avoid the ruts that many longtime users are stuck in. Chief among these, says Katie Fogarty, is “not taking LinkedIn seriously enough.” A former TV news writer and public-relations person, Fogarty runs a consulting service (not affiliated with LinkedIn) called LinkedIn Reboot, coaching executives on how to use it as a tool for advancing their careers.

“Everyone needs a presence on LinkedIn today, but it’s a little like doing your taxes,” she says. “People don’t think they’re ‘good at networking,’ so they put off doing anything about it.” Until, that is, they’re looking for a new job. So the typical LinkedIn profile is just a resume, listing someone’s titles and what they were responsible for in each role so far, and letting it go at that.

“But you can miss out on some great opportunities that way,” says Fogarty. To attract the notice, not only of recruiters, but others who may be looking for your talents — as a conference speaker, say, or a potential board member — your profile needs to portray you in all your true wonderfulness. “The ‘experience’ section should tell what’s unique and special about you, and which accomplishments you’re most proud of,” Fogarty explains. “Then, in the ‘summary’ part of your profile, instead of just identifying your skills, try to give a sense of your personality. The tone should be conversational.”

Your photo matters, too. “I’ve worked with people whose profiles don’t even have one,” she says, sounding mildly shocked. In place of that blank gray head, you need a picture showing you at your professional best, ideally one taken by a professional photographer. Says Fogarty, “Save the adorable vacation snap of you and your kids for Facebook.”

Here are four tips for making the most of LinkedIn that Fogarty calls “the 4 C’s.”:

Calendar. On the theory that what gets scheduled gets done, Fogarty recommends blocking off a regular slot on your calendar — even if it’s only an hour a week, or even every two weeks — to spend time on LinkedIn. Get in the habit of keeping your profile up to date and checking out what your connections are up to, including what’s new in any groups (alumni, professional, corporate) you may have joined.

Communicate. “LinkedIn is a social network, so be social,” Fogarty suggests. Comment on others’ posts, and keep up with connection requests and messages. “The key is to interact and be ‘seen,’” Fogarty notes. A word about sending connection requests: Along with the standard “I’d like to connect with you…” boilerplate, add a line or two about why. “Personalize it,” says Fogarty. “You would never walk into someone’s office without saying hello and then, if they don’t know you, explaining why you’re there. This is not much different.”

Care. Networking, online or anywhere else, is “always a two-way street,” says Fogarty. “If you happen to see a job opening on LinkedIn that seems like a good fit for someone you know, for example, send it along.” Likewise with articles you come across that might interest one of your connections, or recommendations you can add to their profiles. The more helpful you can be to the people you know online, the more likely it is that they’ll return the favor.

Categorize. “A really wonderful and often overlooked tool for staying in touch,” Fogarty points out, is the tag on your profile page — click on the “relationship” button — that lets you separate your connections into groups with something in common. Fogarty, for example, has divided up many of her LinkedIn friends and acquaintances according to whether she knows them from graduate school, former jobs, her current business, or a recent speaking trip to Cambodia. “There some things you want to announce to all your connections, like a promotion at work,” she says. “But then there are other things you want to share just with a specific group of people who are likely to be interested, without sending stuff to people who don’t care.”

One more suggestion: Enjoy. “LinkedIn is fun,” Fogarty says. “Just start using it. Jump in the pool.”

Talkback: Has joining LinkedIn helped your career? If so, how? Leave a comment below.

Have a career question for Anne Fisher? Email askannie@fortune.com.