When you start, the program will pop up a window for you to choose the level you want to play (there are four levels in total). After entering the game, click to start the game. The game will first shuffle the cards, and then generate a certain number of cards according to the difficulty you choose. After eight seconds, the order of the playing cards will be shuffled. You need to click the cards in the original order. If you make a wrong choice, it will show failure and you will have to start over. If you succeed, the game will continue.