To have an excellent pulse you have to see how you grip the pool cue and the best way to practice it is with this free E-book: The 7 Best Bridges in pool and how to win 80% of the time.
You also have to see how you catch in the part of the grip area that you can consult in this super complete post to improve this part of your billiard game.
But a flash tip where I see that most people have problems is that your hand is neither too strong, hanging it, nor too soft, dancing in your hand.
And you must practice with this accessory that you can buy in AliExpress, it is an orthopedic arm which helps you to correct the forearm, arm, grip and shooting line.
This other accessory is to improve the pulse and strength in billiards, it works with a spring where you must insert the pool cue and push it against the band of the pool table, the advantage of this is that in a few days you will notice the difference in your game.
Or if you want the classic part is using a plastic bottle and that the cue goes in and out without touching the sides of the mouth of the bottle, with this exercise you will last longer to get used to it, you will invest more time but it is just as effective.
Finally I give you this exercise, without effects, hitting it in the center pass the cue ball between the red balls and hit the corresponding ball, do it 50 times or more until you master it.