You must be logged in to chat. Log in here, if not already. After you log in, your status to chat will be set to “available.” Change your chat availability on your profile under “Chat Settings.”
The chat box is available on every page at the lower, right-hand corner. Chat is public by default—showing all active logged in users on the left-hand side of the box.
You can privately chat with another user by clicking on the “lock” icon under their avatar. After they accept your invitation for a private chat, you can both chat privately.