To start Riece, you just type M-x riece. Then you will prompted for the name of an IRC server. A typical IRC network may consist of several IRC servers and you will need to pick up appropriate one. Most of IRC networks provide a list of available servers on their Web pages:
If your nickname is taken, you will be asked to use different one. The
initial nickname can be set via the variable riece-nickname. By
default, your nickname is generated from your login name.
After successfully connecting to an IRC server, you can join a channel
and talk with people there. To join a channel, type C-c j. By
the way there is a channel called #Riece on IRCnet, so feel free
to use it for testing.
Now you enter a message and it will be seen by everyone else on the channel. Messages from other people will appear on the top-left window.