Someone

alias c1 { return $+($chr(03),07,$1-) }
alias c2 { return $+($chr(03),14,$1-) }
alias c3 { return $+($chr(03),04,$1-) }
on *:TEXT:!mycolor*:#:{
  if (!$4) { notice $nick Wrong syntax: !mycolor 07 14 04 }
  if ($2 isnum 1-15) { set %mycolor1 [ $+ [ $nick ] ] $2 }
  if ($2 isnum 1-9 && $left($2,1) != 0) { set %mycolor1 [ $+ [ $nick ] ] 0 $+ $2 }
  if ($3 isnum 1-15) { set %mycolor2 [ $+ [ $nick ] ] $3 }
  if ($3 isnum 1-9 && $left($3,1) != 0) { set %mycolor2 [ $+ [ $nick ] ] 0 $+ $3 }
  if ($4 isnum 1-15) { set %mycolor3 [ $+ [ $nick ] ] $4 
    if ($4 isnum 1-9 && $left($4,1) != 0) { set %mycolor3 [ $+ [ $nick ] ] 0 $+ $4 }
    notice $nick You set your colors as $chr(3) $+ %mycolor1 [ $+ [ $nick ] ] This $chr(3) $+ %mycolor2 [ $+ [ $nick ] ] This $chr(3) $+ %mycolor3 [ $+ [ $nick ] ] This
  }
}