Susan Polgar's "Chess Rules of Thumb"

These are the rules of thumb to be applied throughout the entire game.

After every move by your opponent, ask yourself these questions:
1. Can I capture any of my opponent's pieces to gain material?
2. What does my opponent want to do?
a) Am I in check?
b) Does my opponent want to capture any of my pieces?
c) Is my opponent threatening a tactical maneuver (i.e., fork, pin, etc.)?
• Simplify the position by trading pieces when you are ahead in material.
• Avoid doubling your pawns (placing two pawns on the same file).
• Always keep your pawns connected.
• Occupy open file(s) with your rook(s).
• Do not trade a bishop for a knight unless the position is closed (with many pawns and no open lines), or unless you gain some kind of advantage from the exchange.
• Avoid staying in pins.
• Keep your pieces on protected squares as much as possible.

In the Opening
Here are some things to look for in the beginning of the game.
• Control the CENTER (start out by putting at least one center pawn in the center).
• Develop your pieces so that they can attack the center as much as possible.
• Put your king in safety quickly by CASTLING.
• Don't move the same piece twice (unless necessary; i.e., moving away from an attack or recapturing, etc.).
• Don't move your queen out early (usually only after both knights and bishops are developed and the king is safe).
• Connect your rooks by moving out all pieces between them.
In the Middlegame
Below are some of things to look for after you have developed all your pieces.
• Look for targets or weaknesses in your opponent's position.
• Make plans based on the targets and your opponent's position.
• When you have an attack going on the opponent's king, avoid trading queens.
• Keep your king safe, usually behind two or three pawns and near the corner.
• Gain a space advantage.

In the endgame
Here are some things to look for after several pieces (usually including the queens) have been exchanged.
• Try to bring your king toward the center and in play. In the endgame, contrary to the earlier parts of the game, the king should be an active participant, at times even in the attack.
• Try to create passed pawns.
• If you have a passed pawn, advance it. Try to promote your passed pawn to a Queen.
• If your opponent has a passed pawn, make sure you can stop it before it reaches the promotion square (or at least make a counter plan).

Source: Susan Polgar's Chess Blog

jrobichess makes chess videos and has a chess blog along with a personal chess site at http://www.jrobichess.com.