Atomic Habits 8

 Since your body associates feelings and cravings with cues, you can make it associate feelings you want to feel with certain acts. Some writers conditioned themselves to focus when they put headphones in. They didn't even need to play music, their body immediately went, "Headphones are on. Time to focus." It happens with athletes when they do stretches before the game. Their body knows they are stretching and knows that a game will come after, so it goes into "game mode".