How do I automatically make a nick into an operator of the channel

Thanks

Use the /aop command.
/aop #channel nick!*@*

OR if you are on network/server that support ChanServ bot
then you could type
/chanserv aop #channel add user

where
#channel is YOUR channel
user is USER/NICKNAME you want to give aop

note that you can use this command only if
you are SuperOp (SOP) or channel FOUNDER

and using this command ADDS user PERMANENTLY to
AUTO-OP list