I get a lot of invitations to connect on LinkedIn. This is no surprise because it’s a great tool for professionals to connect. What might surprise you is that I say no to a lot of invitations. Sometimes I feel bad saying no, so I send back a little description of the lessons I’ve learned from LinkedIn executives about how to use the service.

Because LinkedIn sponsors Brazen Careerist, I have had the opportunity to pepper LinkedIn mavens with random etiquette questions. So at this point, I have a few opinions of my own. Here’s my advice:

1. Don’t say yes to an invitation from a person you don’t really know.
LinkedIn works best as a way to leverage your professional circle of people you know well or know their work well. I love looking through my friends’ professional networks to get an idea of what introductions I could possibly get from a friend. My friend can say to her friend, “This is Penelope, you should get to know her because of x.” But this only works if my friend actually knows me and the other person well. Otherwise, I may as well make the introduction myself.

In that respect, your network on LinkedIn is really only as strong as your ties to the people in it. You will get more benefits from LinkedIn if you have a network of 30 people you know well than 300 people you don’t really know.

2. Don’t send invitations to people who don’t know you.
I feel like I kinda know Mike Arrington. I know I’d like to have dinner with him (does he ever stop blogging to have dinner?) I read his blog every day, and I know the type of connections he could offer me. But he doesn’t know me. Even if I have emailed him three times and posted ten comments on his blog, he doesn’t know who I am. He probably reads 400 emails and comments a day.

3. Don’t put your email address under your name on your profile.
When you appear in other peoples’ lists, if someone wants to connect with you, they have to go through your mutual connection, or they can email you directly. There is a reason LinkedIn works this way – the point is not to connect with everyone, it’s to connect with people you know. Someone who puts their email address right under their name is announcing that they will connect with anyone, and for the purposes of LinkedIn, this will weaken their network.

4. When you send an invitation, don’t apologize.
I get a lot of invitations that say, “Sorry for the form letter” but you’ll have to trust me that the most well connected, high-level, experienced people I know send the form letter. It’s fine. Also, people send invitations to me that say something like, “Okay, I’m doing the LinkedIn thing.” But it makes you look bad to invite someone to something you feel uncomfortable with, so if you can’t think of something good to write, just send one of the form letters.

5. Remind me how I know you.
Sometimes, I do actually know someone, but I communicate with so many different people every day, that I don’t remember. Yesterday I got an invitation that said, “It was great to do the podcast interview with you today” right before the standard LinkedIn invitation text. That was great. I knew exactly who the woman was and I connected. This also brings up another point, which is act immediately. The best invitations come right after you’ve made one, solid connection with a given person. For example, if you go back and forth in email six times, send an invitation that day.

6. Think about LinkedIn from the other person’s perspective.
Journalists, for example, will be harder to connect with. They are notoriously adept at telling people they have no time to talk. Also, journalists already have good access to a wide range of people. However a journalist will be happy to connect to, say, the managing editor of the New York Times. Know who you’re dealing with and where you fit in and then you’ll understand how well you need to know the person in order to connect. (Note: Here are good ways for Journalists to use LinkedIn.)

7. Keep things a little informal.
LinkedIn is a group of people coming together to help each other. More cocktail party than job interview. So, for example, make your resume a little chatty. The best LinkedIn profiles are a little more casual than a formal resume. I think I could actually fix mine up a bit in this regard. When I read a resume on LinkedIn, I am not scanning to see if I want to hire the person (which is the purpose of the formal resume format). Instead, I would like a sort of cocktail-party introduction about the person and what they are doing with their life. Don’t write paragraphs in your resume, but a short paragraph on LinkedIn is sort of nice.

Of course, this just scratches the surface of the nuances of LinkedIn. For example, if you work remotely, you can use LinkedIn to compensate for less face time. And if you are feeling like a power user, check out Linked Intelligence, the blog about how to use LinkedIn.