Why you need to be on LinkedIn.

I love LinkedIn. Sociologist Mark Granovetter wrote a paper called The Strength of Weak Ties; it's an idea that was later more widely read when Malcolm Gladwell discussed it in The Tipping Point. The brief summary is that weak ties allow you to reach a lot more people and give you a lot more opportunities than strong ties do. Think about when you've gotten a job or a new client and it's been through some kind of an existing relationship. Chances are that it was through a weak tie — not your best friend or your spouse, but maybe through your brother's client's wife or your spouse's tennis partner.

LinkedIn is all about the weak ties. You can use it to stay connected to — yes — your best friends, but also to your former coworkers, high school classmates and the people you met at a business seminar a few weeks ago. Whatever you do, there are people out there looking to do business with you. LinkedIn makes it super-easy for them to find you, and they'll see which contacts you have in common, which puts some social proof on your side.

An example: I recently got a message through LinkedIn from a woman I know socially. She needed some social media help, so she went on LinkedIn and did a search. I hadn't seen her in months and we had never talked about work. She had no idea what I did for a living, but she found my profile and ended up hiring me.

Here are a few quick tips for maximizing your LinkedIn profile. (Groups are a whole 'nother thing and will be the topic of a future post):

Keep your profile complete and up-to-date. You know the headache you get when it's time to update your resumé (and this isn't only an issue for employees; occasionally business owners are asked for them too). Keeping this updated regularly makes it easy, and in many cases you can just direct 'em to LinkedIn. Also great: when you add information (experience, a web site, a photo, etc.), everyone in your network will see it on the main page when they log in. If they don't log in, they'll see your update in the weekly email that LinkedIn send to users.

Include a photo.According to LinkedIn, profiles with photos are seven times more likely to be clicked on than profiles without. I'm of the opinion that you're better off having a not-ideal photo on here than none at all.

If you send a connection request to someone you don't know; please include a personal note. In my opinion, it's OK to send LinkedIn requests to strangers if you also introduce yourself. I've built great working relationships with some people I've met that way; they've written a note telling me why they got in touch, and I think that's totally OK. But it's spammy to send a connection request to a total stranger without even saying hi.