The first 30 rules are origionally from a guy named Reuben Fine. I found them via Stan's message board as posted by the player Knightnite.
3 groups of ten suggestions for aspiring beginner chess players.
TEN OPENING RULES
OPEN with a CENTER PAWN.
TEN MIDDLEGAME RULES
DEVELOP with threats.
KNIGHTS before BISHOPS. (ask Knightnite)
DON'T move the same piece twice.
Make as FEW PAWN MOVES as possible in the opening.
DON'T bring your QUEEN out too EARLY.
CASTLE as soon as possible, preferably on the KING SIDE.
Always play to gain control, of the center
Try to maintain at least ONE PAWN in the CENTER.
DON'T SACRIFICE without a clear and dequate reason. For a sacrificed pawn you must
GAIN THREE TEMPI, or
DEFLECT the enemy QUEEN, or
PREVENT CASTLING, or
BUILD UP a strong attack.
HAVE ALL your MOVES fit into definite PLANS.
Rules of Planning:
A plan MUST be suggested by some feature in the position.
When you are material AHEAD, EXCHANGE as many pieces as possible, especially QUEENS.
A plan MUST be based on SOUND STRATEGIC
A plan MUST be FLEXIBLE,
Evaluating a Position:
AVOID serious pawn WEAKNESSES.
In CRAMPED POSITIONS free yourself by EXCHANGING. DON'T bring your KING out with your OPPONENT'S QUEEN on the board. (just ask TERP)
All COMBINATIONS are based on DOUBLE ATTACK.
If your opponent has ONE or MORE pieces EXPOSED, look for a COMBINATION.
IN SUPERIOR POSITIONS, to ATTACK the ENEMY KING, you must OPEN a file (or less often a diagonal) for your HEAVY PIECES (QUEEN and ROOKS).
IN EVEN POSITIONS, CENTRALIZE the action of ALL your PIECES.
IN INFERIOR POSITIONS, the best DEFENSE is COUNTER-ATTACK, if possible.
TEN ENDGAME RULES
To win WITHOUT PAWNS, you must be at least a ROOK or TWO MINOR PIECES ahead (two knights excepted).
The KING must be ACTIVE in the ENDING.
PASSED PAWNS must be PUSHED (PPMBP).
The EASIEST endings to win are PURE PAWN endings.
If you are ONLY ONE PAWN ahead, EXCHANGE PIECES, not pawns.
DON'T place your PAWNS on the SAME COLOR SQUARES as your BISHOP.
BISHOPS are BETTER than KNIGHTS in all but BLOCKED pawn positions.( But a Knight can combat a bishop in a pawn same side setting-Knightnite)
It is usually worth GIVING UP A PAWN to get a ROOK ON THE SEVENTH RANK.
ROOKS belong BEHIND PASSED PAWNS (RBBPP).
BLOCKADE PASSED PAWNS with the KING.(or a Knight)
-Thank you, Reuben Fine and Knightnite
These tips are as posted by Boardwalker
A. Attack it back or another
Also when your opponent moves a piece then always ask yourself
B. Block it
C. Capture it
D. Defend against it
Thank you Board Walker.
What does it threaten?
What does it open for other pieces?
What can I gain by this move?