2.1. Opening Files If you have a lead in development, open up the position. Open files increase the scope of pieces, especially Rooks. The enemy King can easily find himself in trouble. The opening of a position is also good when you have the Bishops and your opponent has the Knights.
https://lichess.org/study/cEm9IxNu/HIdP9asl#42
2.2. The Peregrination of the King Peregrination – a longer journey or a trip. As a rule, the King does not become an active piece until the endgame. His active play earlier in the game usually stems from the fact that there is a threat of an attack on his position. It is very rare for the King to help other pieces in the attack.
https://lichess.org/study/cEm9IxNu/wH952kfl#83
2.3. Improving the Pieces It is not always easy to find the best move, especially if we do not have a specific plan for the game. In such situations, it may be helpful to come up with the idea of improving one of our pieces. It would be ideal if we could improve our worst piece, but it is not always simple to determine which of our pieces is the worst. What is more, sometimes it may not always be possible to find a better spot for our very worst piece.
https://lichess.org/study/cEm9IxNu/iGkCC2qt#33
2.4. The Transfer of the Queen Being the strongest piece, the Queen can strongly affect the position, but sometimes she can be misplaced, too. Her transfer from one side of the board to the other is often decisive.
https://lichess.org/study/cEm9IxNu/5ZY4KxlF#49
2.5. Occupying the Outpost An outpost is a square that can be occupied by our pieces and cannot be attacked by the opponent’s pawns. The occupation of an outpost in the centre is of great importance, as it gives our pieces the opportunity to create threats both on the kingside and the queenside.
