How to use irc mac?

You probably use specific instant messenger programs like Yahoo Instant Messenger, Google Talk or you use a Mac multi-IM client like Adium or Fire. They're pretty nice, particularly the last two, but none of them are compatible with IRC chat rooms. Procedure: Choose "Connect" and you'll be hooked up to the IRC server in just a few seconds. When you're connected, just choose File --> Join Chat Room and type in the name of the specific conference room that you have been told about. Now, you'll be able to chat away. Once you start running Colloquy, spend some time exploring the various customizations too. It's very nice. Hope that helps you out.