President!

The player to dealer's left starts by leading (face up) any single card or any set of cards of equal rank (for example three fives). Each player in turn must then either pass (i.e. not play any cards), or play face up a card or set of cards which beats the previous play.

A single card is beaten by any higher single card. A set of cards can only be beaten by a higher set containing the same number of cards. So for example if the previous player played two sixes you can beat this with two kings, or two sevens, but not with a single king, and not with three sevens (though you could play two of them and hang onto the third).

It is not necessary to beat the previous play just because you can - passing is always allowed. Also passing does not prevent you from playing the next time your turn comes round.

The play continues as many times around the table as necessary until someone makes a play which everyone else passes. All the cards played are then turned face down and put to one side, and the player who played last (and highest) to the previous "trick" starts again by leading any card or set of equal cards.
(http://www.pagat.com/climbing/asshole.html)

Cards rank: 2 > A > K > Q > J > 10 > 9 > 8 > 7 > 6 > 5 > 4 > 3

Play on English and Portuguese.