What’s the first thing you do?
Would you loudly announce yourself? Start thumping your chest and bellowing, “I sing a song of myself!”
Probably not (well, hopefully not!).
No, instead you listen, smile, maybe try the dip.
So, why do anything differently online?
When you join a forum or a Ning group, listen for a while. Introduce yourself. Comment (politely) on some ongoing discussions and conversations. Offer useful advice to people who are looking for help.
Don’t yell. Don’t spam. Don’t be “that guy.” You know, the one with the loud voice, who goes on and on about himself.
Nobody wants to hear a monologue, unless it’s Jon Stewart’s. Even comedians stop and listen for feedback (is the audience laughing and smiling or throwing rotten veggies?).