Enter in the amount of cups (3-13). Then the game will begin. The more cups there are, the more times the cups swap. After the cups have stopped switching, move your mouse over a cup to lift it up. Try to find which cup the ball was under. Tips: The cup with the ball underneath will switch more often. Two of the same cups will never switch twice.
Just a little game I made on the offline editor while the wifi was down. It took me less than 15 minutes.