Several Shots Ahead

While you should never run out the timer (I know, I repeat myself), you should also try to begin seeing each frame several shots ahead of where you are. Don’t just react to where the balls are on the table during a given turn, and don’t just shoot wildly in the hopes of disrupting the current state of the table (unless you have to.)
Instead, assume that the cue ball is the only thing that’s going to move over the next several shots. Where do you need the cue ball to be, in order to pot the most of your own color? In this way, the game of pool is a lot like chess. An experienced player will take their time learning the lay of each shot, but a master will know the lay several shots ahead of the current turn.