Tripsit provides a tor hidden service to allow anonymous connections. You will need to connect without tor at least once to register your nickname.
Connect without tor and register a nickname with NickServ (More information Here)
Configure your IRC client to use Tor as a proxy. Directions for individual clients Here
Start the tor daemon (Or Vidalia control panel)
Set up your client to connect to fgkjgjce66ymgx2g.onion with SSL on port 6697. Configure your client to identify with SASL or you won't be able to connect. (Info on how to configure SASL can be found Here
Connect! It may take some time to negotiate a connection through the tor network, so be patient! If there's any issues, join #help or PM Physical.