It's clear, for example, that finding a square numbered 8 means that all eight adjacent squares contain mines. If the square remains blank, there are no mines in the surrounding squares. To mark a square suspected of containing a mine, the player clicks on it with the right mouse button, putting a little flag on the square. The first few moves require one or more wild, potentially fatal guesses. That choice depends on the sorts of things that can happen on subsequent moves, which are not the same for every starting position.
Experts recommend beginning somewhere in the middle.
There are a few situations in which you may be forced to guess a mine's location to complete a game. It doesn't take long to develop strategies for playing and beating the game. In general, clearing a board rapidly requires a form of pattern recognition. For example, if an uncovered square is labeled 1, and there is only one covered square touching it, that covered square must be a mine. In fact, if you have found all the mines around a given numbered square, you can uncover the remaining squares by clicking the numbered square with the left and right mouse buttons simultaneously.