Click the reset button (the arrow that is nearly a circle) to choose a new number, it's best to click random if you don't want to know what your number is already! Then click the other arrow that points up, that saves the random number, and you can start playing! The aim try to work out what the number is by typing in numbers and seeing by the number that comes up at the side how many of them were correct. Make sure you press the arrow pointing up each time you type in a number.