The more spins you have, the bigger the deflection/angle of the ball in a certain direction. The amount of Cue Spins depends on the Cue Stat. If you tap on the Cue Ball, you will be able to decide where to hit it to give the ball a different spin/direction after it hits the rail or a ball. When you are at the desired location let go of the left side of your mouse. If you are playing in the web version, just hold the left side of your mouse and move it to where you would like to place the cue ball. Once you have found the perfect spot, just release it and be ready to aim! If you are playing in the mobile version, to move the cue ball you need to tap on it and drag it to the desired position.
You are allowed to move the cue ball if you are the first one to break (only on the break line) or everywhere on the table if the opponent commits a foul (for instance if they pot the cue ball).