The first ticket is obtained by talking to the child, she will ask you to find her teddy bear, which can be found in the next door on the left, return this teddy for a ticket.
The second ticket can be found upstairs in the bar.
First he requires you to turn some music on, simply by clicking on a number on the jukebox. The man will then ask you to make him some drinks.
The drinks on the counter are in this order: Cola, Tonic, Orange Juice, Vodka, Rum & Gin
The third ticket can be found at the front of the ship. simply talk to the lady at the front of the ship, you earn it from just chatting with her.
The fourth ticket can be found downstairs in the coal room, you can earn this by simply chatting with the man.
Boom, Achievement unlocked!