Can you clear the mines and make this board safe? To play Minesweeper, choose a board size. You can choose 25x25 or 16x16. The larger the board, the more difficult the game. On the right side of the screen, you will see how many mines there are. Get started by clicking on the board. You should see numbers appear. The number in a square tells you how many mines are in the eight squares surrounding it. By looking at numbers that are close together, you can begin to figure out which squares have mines and which are clear. To mark a mine, hover over a square and push the space bar.