MODE <nick> <+|-><modes>

Usermodes:

     USERMODE     DESCRIPTION
-----------------------------------------------------------------
         +o     - Designates this client is an IRC Operator.
                  Use the /oper command to attain this.
         +i     - Designates this client 'invisible'.
         +g     - "caller id" mode only allow accept clients to message you
         +G     - "soft caller id" mode - same as +g but automatically allows
                  anyone who's in a common channel with you to message you.
         +w     - Can see oper wallops.
         +B     - Marks you as a bot in /whois.
         +C     - Prevents you from receiving CTCPs other than ACTION.
         +D     - Deaf - ignores all channel messages.
         +Q     - Prevents you from being affected by channel forwarding.
         +R     - Prevents non accept unidentified users from messaging you.
         +V     - Prevents you from receiving invites.
         +Z     - Is connected via SSL (cannot be set or unset).