I played this very frequently in Brazil. It was extremely quick, easy and a LOT of fun especially for larger groups. It's incredibly strategic yet extremely simple. It's one of the best card games for larger groups in my opinion.
A deck of cards and about seven tokens per player; a pen and paper to note scores. The tokens can be anything; we used corn.
Win by accumulating the most amount of points by game end. Win points by getting your bets right.
At game start each player receives one card. The remaining deck gets placed face down. One card is drawn from the top and placed face up. The suite of this card is now the trump suite.
For each subsequent round players receive one additional card at game start. So on round two players receive two cards each; on round three players receive three cards each, etc...
The deck is reshuffled for each round and a new trump card is drawn.
The highest round is seven. At seven you reverse the count, and continue back to one. The game then ends after 13 rounds have been played (1,2,3,4,5,6,7,6,5,4,3,2,1), and the scores are tallied.
Step One: Bet
On every round each player makes a secret bet by placing the number of tokens they wish to bet in their hand. Keep the number of tokens hidden from other players. The number of tokens bet should reflect the number of hands a player thinks will win. When all players have decided on a bet they release their tokens at the same time. It is possible to bet 0.
Be sure to keep the tokens used for the bet separate from the original token stash. Bets are not mixed. A player's bet remains separate from that of others. Tokens are never transfered between players.
Step Two: Play
Play commences as with any normal card game. The holder of the highest card of the first suite played wins the hand, unless someone has a trump card. Trump cards can only be used if the player has no cards of the same suit being played. If a player has neither, he plays whatever he has to no effect. If a player does have a trump card, he or she can choose not to use it.
On rounds that have more than one hand, the winner of the hand resumes by playing the suite of their choice.
Step Three: Score
When the round ends, which is when all cards have been played, each player tallies the number of hands they won. All players get one point for each hand they won. Those who managed to match their bet to the number of hands won receive a bonus of 10 points each.
So, if I bet two tokens and at game end I have won two hands, I receive a total of 12 points.
If the number of tokens bet is less than the number if players, the dealer must add an one additional token to his bet. We don't often play this rule, but it is rule.