When no pairs can be made click the blue button with a white arrow on it to shuffle the deck of cards.Click on kings or pairs which add up to 13.Remove all cards from the pyramid by joining cards which add up to 13.
You can scroll through them using the left and right arrows near the instructions, or click the blue and white play button again to start the game. Click on Kings (valued at 13) and click on pairs of cards which sum up to 13 to try to remove all cards from the pyramid starting with the exposed cards in the bottom row.