Imbalances
Compare material, pawn structure, space, king safety, development, bishop pair, weak squares and initiative before choosing a plan.
Weak Squares
Recognize squares a pawn can no longer defend and build a plan around occupation, exchange of defenders and restriction.
Outposts
Use stable squares for knights and other pieces only when the outpost serves a real target or break.
Open and Half-Open Files
Place rooks on files that lead to entry squares or targets, not merely files that happen to be open.
Space Advantage
Use extra space to maneuver and restrict the opponent while avoiding overextension and unnecessary pawn pushes.
Prophylaxis
Ask what the opponent wants next and prevent it when doing so improves your own position or removes counterplay.
Exchanges
Trade pieces based on which side benefits from simplification, space, weak squares, king safety and endgame structure.
Two Weaknesses
Create or attack a second target when the defender can hold one weakness with all pieces concentrated around it.
Good Bishop and Bad Bishop
Judge a bishop by the pawn structure and available diagonals rather than by a static label.
Color Complexes
Exploit a network of weak squares on one color after the corresponding bishop is absent or pawns are fixed poorly.