Well, I use IceChat. There's a button at the top of IceChat thats called Server Editor. I can click that, and change my indent name, along with the:
Server Name:
Server Port:
Nickname:
alt. Nick:
Away Nick:
Indent Name: (which is IceChat77)
Full Name:
Quit Message:
Try and find a button or command near this information above to change your indent name. A client is a program you use the IRC. My client is Icechat. Client = program.