Having three or more people vouch for your work on the site is smart, Gowel says. (He has 18 recommendations.) One approach is to e-mail current and former colleagues and ask (Gowel says you might even send a draft of a recommendation to make it easier for them).
But if you write an unsolicited recommendation for someone else on the site, when they approve it so that it appears on their profile, LinkedIn will ask them if they want to return the favor. Its almost the guilt approach, Gowel says. And it works.