As the job market continues to sour, it is important to take advantage of all available tools to keep up with your personal and professional network. So if you’ve been joining social networking sites and never taking the time to complete your profile — or if you’ve been hitting the delete button when friends and colleagues invite you to connect on a new online platform, now is a good time to start paying more attention. Here are a few things to think about as you take the plunge or take your social networking to the next level.

LinkedIn has taken hold as the standard for most professionals, but also consider spending time on sites catering to your own industry or profession. Keep up with the trade press in your field to figure out where your peers are congregating online. Specialized communities exist for just about any industry or interest group — like NurseLinkup.com (for nursing professionals), Model Mayhem (for models and photographers), Mediabistro.com (for media professionals) or Lawyrs.net (for lawyers). Have a look at this excellent list of other niche social networking sites.

Though online social networking sites are newish, the same rules of old-fashioned in-person networking apply. Build your reputation as a giver, rather than as someone who is always asking for favors. If people in your network, for example, ask for help or introductions, check in periodically and respond when appropriate. If you’ve shown that you are a giver, people will rally to help you when you have a need to tap your network.

Use these sites to showcase your experience and achievements. If you or someone in your organization has recently given or heard a terrific presentation, won a case, published an article or appeared on television, post something about it. If you do this in the spirit of sharing good information with others — like this video about the current economic situation that Ramit Sethi, a personal finance blogger, distributed via Twitter and other tools — you’ll have the perfect marriage of self-promotion and sharing good information with your online colleagues and fans.

Build your presence on these networks when you’re not looking for a job. Make sure that your profile is up to date. Periodically check to see if there are people you know that you could be connecting with. Be responsive to requests from your network. Should you then need to look for a new opportunity, your network will be well tended and it won’t be awkward to connect with people who can be of help.

Finally, a few words of caution to keep in mind:

When you create a presence on a social networking site, take the time to learn how to use it properly. If the site offers an online tutorial, do it. If possible, find a friend or colleague who is already part of the community to give you a primer on the site’s etiquette.

Do not join every social networking site that hits your radar — there’s a reason the phrase “social networking overload” has been cropping up a lot on blogs lately. As with professional organizations or clubs, it is hard to be a real contributor when you are involved with too many groups. That said, you might find it helpful to join a handful of sites and then choose one or two on which you will be more active.

Social networking sites make it easy to contact people, but be mindful of your online manners. Do not try to connect with people you don’t know personally. Do not use these tools to stalk or send spam to people who haven’t been otherwise responsive to you. And make sure to review and follow the guidelines of any community that you join.

Note: I have cited Linkedin here and in a few other recent posts without mentioning that The New York Times has a strategic partnership with LinkedIn. I have been using LinkedIn for quite a while now, well before I knew about its relationship with The Times, so I don’t believe that relationship has made me more or less likely to write about the site. Nonetheless readers should know about the relationship.