The Ghost-Ball Method
Visualizing where the cue ball must be at contact to send the object ball where you want.
The core idea
To send an object ball into a pocket, the cue ball must arrive at one exact spot: the point where, if you placed a second ball (the "ghost ball") touching the object ball on the line from the object ball to the pocket, the two balls would be frozen together. Aim your cue ball at that imaginary ghost ball's center, and a true, correctly-struck shot sends the object ball along the intended line.
Building the picture
Start by drawing a mental line from the center of the target pocket through the center of the object ball, and extend that line the same distance again beyond the object ball — that far point is where the ghost ball sits. Since ball diameters are consistent, with practice you learn to "see" that spot at a glance rather than measuring it out each time.
Where it breaks down
Ghost-ball aiming is a geometric idealization: it assumes a perfectly straight, level, center-ball stroke with no spin-induced throw or deflection. In practice, spin, speed, and cut-induced throw shift the object ball's actual path slightly off that ideal line, especially on thin cuts. Treat the ghost ball as your starting reference point, then adjust for those real-world effects with experience.