To sign captain, form your dominant hand into a claw shape and tap it onto your shoulder. It is like you are indicating the "epaulette" or shoulder piece on a captain's suit, whether he (or she!) is the captain of a ship, an airplane, or the army.
Teach your toddler the captain sign when you are playing Captain's Orders or any other pirate game at home, or in preparation for a children's party.
This is a useful flash card taught best in preparation for a game or activity involving ships, captains, pirates, and sea treasures.