It is easy to overlook critical responses to a threat. Having a disciplined approach for the assessment of possible responses can go a long way to ensure that you play your best. For myself, I have a set of mnemonics that I apply to minimize the risk that I overlook something. To illustrate this method, consider this position with white to move. Black is threatening white’s queen with his knight. What are all the moves that black might consider in response to this threat that might avoid the loss of material?
First, white can check black’s king with Ra8.
Second, white can counter-attack black’s queen with Ra7.
Third, white can capture the knight with Bxe4.
Fourth, white can move his queen so it is no longer being threatened.
Fifth, white can pin the knight with Re1.
So we have check-counter-capture-move-pin. Repeat that a hundred times so you won’t forget it.
My general mnemonic is check-counter-capture-guard-move-flight-intercede-precede-flight-pin. I won’t go into what all this means now, but it’s easy to remember and easy to apply at the board.
In the above example, the queen is attacked by a knight. If it were attacked by a bishop, then the mnemonic would be check-counter-capture-move-intercede-pin, since one could intercede a piece between the bishop and the queen (if there were available squares to do so).
If a bishop were attacking the knight, then the mnemonic is check-counter-capture-guard-move-intercede-pin, since there is the option of guarding the knight.