The abilities of Persons are depicted on the top part of their card on the banner. The victory points you gain are depicted on the little shield to the right of the ability banner.
When you act - either as the active player, or during your chance on another players turn - you can use all abilities of Persons in your personal display. If you have multiples of one type of card, their abilities will stack. Should you have 2 Mademoiselles, for example, you will be able to hire Persons at a 2 gold coin discount.
Settlers, Captains, Priests (5 times each) Jack of all Trades ( 3 times)
To be able to help claim an Expedition you must be able to discard these types of cards from your personal display. The ability banner is a little darker to signify this. The Jack of all Trades is a Joker type of card and can be discarded instead of a Priest, Settler or Captain.
Trader ( 2 of each color)
The player will gain 1 more golden coin if he has a Trader of the appropriate Ship color in his personal display.
Sailor (10 times) / Pirate ( 3 times)
With the depicted Swords, Ships can be repelled. (see Phase 1: Discover)
Admiral (6 times)
Whenever it is your time to take a card/cards during Phase 2: Trade & Hire and there are currently 5 or more cards in the harbor display you immediately gain 2 coins.
Jester (5 times)
If you are currently not the active player and during a Phase 2: Trade & Hire it is your turn to take a card - and there are no cards left in the harbor display, immediately gain 1 coin. Should a player forfeit his turn during a Phase 1: Discover and the 2nd Phase will be skipped, all players with a Jester gain 1 coin.
Governor ( 4 times)
Whenever it is your time to take a card/cards during Phase 2: Trade & Hire you may take 1 more card from the harbor display. If you are not the active player, you have to compensate the active player with 1 coin for each card taken.
Mademoiselle (4 times)
The hire cost of a Person is discounted by 1 coin. The cost cannot be discounted to less than 0.