Until you have this shot mastered, it will be the most important drill you shoot. When hit perfectly the centre of the cue ball should hit your tip. Centre ball striking is absolutely vital to playing well in any cue sport. Get to know where the centre of the ball is and be confident that you can hit it whenever you want. Begin every practice session with this shot. By ensuring you are stroking well at the beginning of every session you are setting yourself up for success.
Shoot along the baulk line (along the width instead of the length of the table).
When the cue ball is consistently hitting your tip dead centre, add in other balls beside the path of the cue ball as goalposts to ensure that you are not putting any side on the ball.
Experiment with different cue ball locations, try frozen to the rail and see if you are still hitting perfectly.
For an extra challenging version, place a ball in the middle of the table, hit it to the short rail so it comes back and hits the cue ball back into your tip. If you can do this your stroke and alignment are nearly perfect!
Mark the spot on the rail that you need to hit with a piece of chalk.
Focus on a slow and controlled stroke. Poking or jabbing the ball will almost inevitably lead to the cue ball travelling offline. Smoothness is key.
Use a striped ball so you can see any accidental side.