Punch Cards: Official Site

5-Play Rules:

Make sure you know the Quick Play rules.

Each player needs five different Punch Cards. (You can't have duplicates, though you may use some of the same cards as your opponent.) Players choose their first combatant in secret. Play one game exactly as you would in the Quick Play version.

The winner of the quick game adds the difference in quick-numbers to his running score. For example, if the quick game was played for high, and the difference between the highest numbers was 12, then the winner of that game scores 12 points.

The loser must remove his losing card from the game. On the next round, the winner of the previous round must use the same card he just played, but the loser can choose from among his remaining cards. Repeat the quick-play game with the next pair of cards, and so on.

The game continues until one player concedes or until one player runs out of cards. At this point, the player with the highest score wins.

Ties: In the event of quick-game tie, both players score zero and both players can chose a new combatant for the next round. In the event of a total game tie, the player who won the quick game most recently wins the entire game.

If that's not enough, we also have a set of all-weekend Convention Rules. Check 'em Out.