Prep.

A basketball coach who shares a name with a popular chess piece said:

"The key is not the will to win... everybody has that. It is the will to prepare to win that is important." - Bobby Knight

Repeatedly assess/evaluate the position when you are preparing. Give yourself 3-4 candidate moves when preparing. Look at loose pieces, checks, threats, and more, while you are preparing. Do all of the systematic thinking while preparing, and it will happen naturally in your tournament games.

Preparing = Studying chess. Examples: Looking at famous games. Solving hard puzzles (the ones that might take 5 minutes to solve). Attending a challenging chess class.

PREPARATION PREVENTS POOR PERFORMANCE*.

* Usually the quote you hear is "prior planning prevents poor performance" but you know... I'm trying to use a high frequency word.