My Sir gave me a series of tasks, all related, that we both enjoy very much.
First, I had to buy black and white marbles or as close as I could find (you can use checkers or whatever else you have handy). I found them at Walmart for cheap.
Second, to start I had to write ten punishments and ten rewards on 3X5 cards. I have since had to type them up and print them on differently colored paper - red for punishment and blue for reward.
Thirdly, Sir made a leather bag to hold the marbles and if I displease Sir he will take out a white marble and if I please him he will take out a black. When he chooses (sometimes he will allow me if I ask) I draw a marble from the bag. Black means I must blindly pick a punishment card and a white marble means I get to blindly pick a reward card.
The cards are particularly effective because I am the best person to know what will truly be a punishment for me and what things I find most rewarding. Several cards I wrote surprised Sir, and have increased our communication, understanding, and intimacy. Regardless of what you're into, there are a few universal cards that can add some fun and chance into your game:
Draw two more cards
Remove one punishment card
Remove two reward cards
Draw another marble
My favorite reward card is the one where Sir must write two new rewards and two new punishments for the deck.
Enjoy!