Connect to Fleetchat IRC using: 

(Please note that if you connect directly to a server and that server is down, you won't get onto Fleetchat. That's why we suggest using our default of irc.fleetchat.org)

All connections are port 6667
Set your connect time (if available) to 45-60 seconds.

Then from there, just type: /join #<channelname>, where <channelname> is obviously the name of the channel you want to join, sans the brackets. For a listing of available channels, consult the "Channels" Page or type /list when you are on Fleetchat.