Reading.
Reading isn’t a distraction or diversion, at least not the sort of reading that leads to reading long lists of minutea about what has been read, collections of details without any context. Good reading leads the reader to explore the inner parts of his mind, to become familiar with them in more than just an instinctual way, rather like how when moving to a new city, you might come to find your way by memorizing turns, a left here and then two rights, and recognizing landmarks and generally feeling around for familiar things like a blind person until you arrive at your destination, but then after time you start to learn the names of the streets, how they flow together and the personalities of each, until one day you are suddenly able to make spontaneous connections and routes, and your trust in the city is cemented, because it’s no longer a place that you fills spaces between your departures and arrivals but a complete thing in itself.