Errors have nothing to do with luck; they are caused by time pressure, discomfort or unfamiliarilty with a position, distractions, feelings of intimidation, nervous tension, overambition, excessive caution, and dozens of other psychological factors.

Under no circumstances should you play fast if you have a winning position. Forget the clock, use all your time and make good moves.

Patience is the most valuable trait of the endgame player. In the endgame, the most common errors, besides those resulting from ignorance of theory, are caused by either impatience, complacency, exhaustion, or all of the above.

Sometimes players need to gain time on the clock by repeating the position, but most often its purpose is to wear down the opponent psychologically.

Since your mental state can have such dramatic effects on your body, obviously your physical condition can affect your mental well-being. It follows that regular physical conditioning should be part of your overall chess training.

According to such great attacking players as Bronstein and Tal, most combinations are inspired by the player's memories of earlier games.

The business of the endgame is maneuvring to control critical squares, advancing or blockading passed pawns, preparing a breakthrough by the king, or exploiting the subtle superiority of one piece over another.