LinkedIn is a Web 2.0 networking site that’s all about business. However, if you just slap up a quickie profile, send out a few invitations, then rarely visit the site, nothing much will come of it. Here’s how to get as much out of LinkedIn as you put into it.

TAG YOURSELF In addition to making sure your profile is painfully complete and up-to-date, consider the keywords someone might use to search for a person with your qualifications. Add these keywords to your profile to make it easier to find among the 10 million-plus others on LinkedIn.

GET RECOMMENDATIONS Ask people whom you've worked for and with to write short recommendations for you by going to the Request Recommendations page, and selecting the contacts from your network. According to LinkedIn, users with recommendations in their profiles are three times more likely to receive relevant inquiries and offers of work.

PUT YOURSELF OUT THERE Include a link to your LinkedIn profile in your email signature, so people can quickly check your resume and recommendations. Allow your LinkedIn profile to be indexed by the major search engines too. Go to Profile, click Edit My Public Profile, then create a Public Profile URL (type your name in the field provided and make sure "full view" is selected).

EXPAND YOUR NETWORK Establish your own guidelines for accepting invitations too add people to your network, and keep your own guidelines in mind when you send invitations to others. Most people won't accept invitations from total strangers. If you want to be added to someone's network because you think that your connections could be mutually beneficial, search their network to see if you have a friend or associate in common who can introduce you via LinkedIn.

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ASK AND ANSWER LinkedIn's Answers service allows members to pose or answer questions. Providing solid, helpful answers to the queries posted here is another way to extend you network. Asking interesting questions could spark a meaningful conversation as well. Self-referential questions like, "How can I find a job?" are frowned upon, for obvious reasons.

LinkedIn's Answer section is a great source of information and a good way to connect with people in a specific industry.

GATHER 'ROUND If you belong to a professional or alumni organization, look into LinkedIn for Groups, which has special features that allow members of an organization to expand their personal networks within and beyond the group. Browse through the Groups section to see if there is a LinkedIn group that you’re qualified to join. Or, if your group qualifies - it must have an "existing member base or affinity (and) serve a business or professional purpose" - start your own LinkedIn group. Go to the LinkedIn FAQ and click on Groups for details.

You can even hook up with other professional service providers - lawyers, doctors, plumbers, contractors - recommended by people in your network.