On your turn, click and hold on left mouse button and a cue ball will appear in the upper left corner of your screen. This is used to control the spin that will be applied to the cue ball. The blue dot indicates where the cue ball will be struck by the cue stick.
To change or move the indication dot, click and hold the left mouse button while moving your mouse. Once the left mouse button is released, the indicator will be locked in that position. (The indicator dot resets after each shot) Adjust the spin of the ball to try difficult technical shot.

On your turn, click and hold the right mouse button while moving your mouse to adjust your cue angle. By doing so, you will be able to achieve difficult masse shots. The more angle you give to your cue, the more pronounced the masse shot will be. (Your cue angle will be reset after each shot)
It's possible to raise your cue angle like the picture shown below.

Press and hold the ALT key while moving your mouse up and down to adjust the Viewpoint level.

The distance of your view will change if you move the mouse up and down.
If you move the mouse up, your View will zoom in and if you move the mouse down, your view will zoom out. (For scrolling mouses, the scroll button will also work in the same manner)

While pressing Ctrl key, move the mouse up and down to hit the ball.
If you press the Ctrl key, the cue will shake left to right. The cue stick will wobble more for farther shots and less for closer shots. The wobble of the cue is also influenced by the quality of the cue stick. The power of the shot is influenced by how quickly you move the mouse, your level and the quality of the cue stick.