I don't see why you would want a script that replys to someone else's nickname but here you go.
Code:
on 1:TEXT:*:#: {
  if ($nick isin $1-) { commands here. }
}

on 1:TEXT:!bot*:#: {
  if ($2 == $null) { notice $nick Valid syntax: !bot [on|off] }
  if ($2 == on) { msg $chan The bot has been activated | .enable #bot }
  if ($2 == off) { msg $chan The bot has now been de-activated | .disable #bot }
}

#bot on
Your commands and events here.
#bot end


For security purposes it is advised that you use "Access Levels" /help Access levels.
If you don't know how to do this simply.
/guser 100 NickName 3

So instead of on 1:TEXT:!bot*:#:
it would be on 100:TEXT:!bot*:#: