Pick a nickname, then tell NickServ to register it.
- Choose a nick: type
/nick YourNickName
- Register it:
/msg NickServ REGISTER password email@example.com
- Check your email if prompted and follow the confirmation link/code.
- Next time you connect, identify:
/msg NickServ IDENTIFY password
Tip: /msg NickServ HELP
shows more options (password changes, recovery, etc.).