If you have ever looked for a job or are in the market for one now, you've probably taken some obligatory steps, such as polishing your résumé and combing job boards.
But if you aren't integrating social media into your job search, you are depriving yourself of a powerful tool. Of course, it's important to use the right sites, and job-search experts say the so-called Big Three—LinkedIn, Facebook and Twitter—are your best bet because of the hordes of recruiters and hiring managers who hang out there.
"There are dozens of other social media sites and niche tools, but unless the employers are out there on those sites, it doesn't make a lot of sense to spend your time there," said Laura Smith-Proulx, a Denver-based executive résumé writer and job-search coach.
It probably comes as no surprise that having a LinkedIn profile is practically mandatory these days for job seekers. In 2014, 97 percent of U.S. recruiters used LinkedIn, while 21 percent used Twitter and 19 percent used Facebook, according to a study by social recruiting firm Bullhorn Reach. Last year, 71 percent of U.S. recruiters used LinkedIn exclusively (out of the three sites), up from 64 percent in 2013, according to Bullhorn.
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A critical first step when it comes to using LinkedIn and other social media sites to land a job is to figure out exactly what kind of position you want and which of your skills and experiences are likely to get you hired for that kind of role. Armed with that information, you should work to create an online presence that reflects what job-search experts call your "personal brand."
One of the best aspects of LinkedIn is that the site gives users the opportunity to highlight their achievements by uploading work samples to their profile pages and adding "rich media" files, such as blog posts, videos and links to websites featuring their work.
"Your online profile has to speak to the audience that you want to attract," said Kevin Grubb, an associate director specializing in digital media and assessment at Villanova University's Career Center. "It should reflect the type of job you want and the types of companies you want to work for."
It's important to create a top-notch LinkedIn profile, but staying active on the site is also critical. You can use LinkedIn to search job listings, stay up to date on companies that interest you by "following" them and to identify possible networking opportunities within those companies by leveraging your "connections" on the site.
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You can also use LinkedIn's publishing platform to position yourself as a thought leader in a certain industry or to post regular status updates from the site's home page to share interesting articles or links to professional events you plan to attend, among other content.
"It's a social network, so social activity has to happen," said Hannah Morgan, a job-search strategist and founder of CareerSherpa.net. "Just because you build a profile doesn't mean recruiters will come."
Facebook can also be a powerful job-search tool, despite the widely held belief that it's simply a forum for people to communicate about our personal lives. Your "friends" on the world's largest social network are probably some of your closest allies, and such people are likely to go out of their way to help you by alerting you to openings and introducing you to high-value contacts, Morgan said.
If you want to let only certain Facebook "friends" know that you are looking for a new job, you can send private messages through the site, as opposed to posting that information on your page. Your contacts on Facebook, said Morgan, are typically "people who really want to help you and know you best of all."
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Some companies use Facebook and other such sites to roll out job listings in order to give users of social media first crack at those opportunities. Of course, employers also use social media to vet job candidates for both qualifications and cultural fit.
Job-search experts say it's OK to let a little of your personality shine through in your social media activities, but political rants, copious spelling mistakes, bad grammar and the regular use of profanities are the types of things that can work against you.
"You shouldn't post something unless you are really sure you want everyone to see it," said job coach Smith-Proulx. "Some recruiters specialize in digging up what we call digital dirt."
Twitter has some distinct advantages as a job-search tool. For one thing, it is easier to connect with hiring managers, thought leaders and others in your field on Twitter than on Facebook or LinkedIn because the micro-blogging site is essentially an open platform. Many Twitter users don't activate privacy controls that would require people to request permission to follow them. Twitter users can also send direct messages to each other.
"Twitter gives you access to what people are thinking," said Grubb of Villanova. "It's an excellent tool for getting to know someone new and networking."
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While LinkedIn, Facebook and Twitter tend to pack the most punch as job-search tools, other sites—like Pinterest, YouTube, Instagram and Snapchat—can help creative types, such as photographers and fashion designers, to show off their talents to potential employers.
Ultimately, though, job seekers should hedge their bets by using every tool at their disposal, including working the room at networking events, perhaps armed with some information gleaned online about attendees they'd like to meet.
"It's all about using a combination of different [job search] vehicles," said Dan Schawbel, founder of WorkplaceTrends.com, a research and advisory service for human resource professionals.
"Social networking is not enough," he explained. "You don't know what will work for you. So it's best to diversify your time."
—By Anna Robaton, special to CNBC.com