Here’s how we do IRC chats here at [squarepegalliance.net]:

1. Find yourself an IRC client. For Windows, we recommend mIRC; for Macs, we recommend Colloquy. [We have no recommendation for Linux users: if you use Linux, you don't need an IRC recommendation from us.] mIRC does have a registration fee after the demo period expires, and while we urge you to support shareware, that’s on your end and not ours. Colloquy is free.
2. Figure out how to do basic stuff with your IRC client: joining rooms, etc. IRChelp.org is totally your friend here, folks.
3. Connect to any Undernet.org IRC server.
4. Join the appropriate room. Our room naming convention has traditionally been #firstnamelastname—for example, a Katy Bowser chat would be held in #katybowser. Simple enough, eh? This is where the actual chat will take place.
5. Join the chat’s backchannel if you like. Our room naming convention has traditionally been #firstnamelastnameback—so a Katy Bowser backchannel would be #katybowserback. The backchannel is always unmoderated, so you can have entire discussions while you’re waiting for the chat to progress.
6. Message the chat moderator to ask a question. It’s best to go ahead and ask the chat moderator your question when you message them: that way they can not only slot you based on order received but also put like questions together to give the chat some flow. Usually, some text like /msg gfmorris I'd like to know what Katy's plans are for a next album: where she'll record, etc. will work the best.
7. Hang out and have fun. That’s the reason we do these chats—they’re supposed to be fun. The only person not having fun is your harried moderator, who is trying to wait on everyone all at once. Be nice to the moderator.

Transcripts are always posted as soon as is feasible after the chat; if you miss one, you’ll still be able to find out what was discussed.