The aim of the game is to get rid of all your cards. For that, you have to make combinations of cards (three of a kind, four of a kind, straight) and lay them on the table.
To lay cards for the first time, your combinations must represent 31 points. Once you have laid your cards on the table, you will be able to use your cards to complete the combinations already there.
When it is your turn, you have to draw a card from the stock or the discard pile, and, in order to complete your turn, you have to discard a card.