Spin, Spin, Spin

That little cue ball in the corner of the screen? It’s there for a reason. If you want to disrupt your opponent, make a tricky shot, or otherwise display (or practice) some finesse, tap that cue ball, rotate it according to the little red indicator that shows up, and then shoot.
It’ll apply a trajectory spin to the cue ball and keep it from moving in a predictable, straight line. If you make your shot (which should always be the goal) then you can use spin to set yourself for shots that wouldn’t otherwise have been possible.