If all of you are approved members, you can use #Ellounge. Simply type /join #Ellounge
You can also create channels of your own. Type /join #Channelname (the # at the start of the channel name is mandatory), and have the others do the same. You best tell them the name of the channel in PM, since anyone can join it. The first one to be in the channel, will be the channel operator, and have full control over the channel.
Also keep in mind that anyone could find out about the channel by means of the /whois and /list commands. A good idea might be to type /mode #channelname +s to make your channel secret. Only the channel operator (the person to be in first) can do so.
If you want to use a specific channel on more than a single incident, it might be wise to register the channel, and put up several additional options. Mention my name on IRC, and if I'm around, I can help you with more advanced features, if you'd like me to.