You'd never think there was very much involved with racking the balls. To rack the balls, you place them within a frame — either triangular in shape or in a diamond shape depending on the game you're playing. Position the rack at the proper point on the table and place the balls inside. When the balls are touching each other, lift the rack from the back end to the front end and the balls should stay in their racked formation.
At this point, the player to go first will break the rack by aiming at the head ball (the ball in the apex of the triangle) and striking as powerfully as possible with two goals in mind: to scatter the balls and to pocket at least one ball on the break.
Every game should start with a tight rack. That means that all the balls should be tightly packed within the rack so that they are touching one another (or “frozen”). The rack should then be aligned properly on the table. If the balls are not racked correctly, the break will be flawed, which means that the balls will not scatter on the table, which lessens the chance of pocketing a ball.
It is traditional for the opposing player to rack the balls for the starting player (the one who breaks). If you are playing against an unethical sort, he or she may try to hoodwink you and rack incorrectly. But you can agree to rack your own balls before the game begins. It's up to you and your opponent.
How do you spot a bad rack? Look at the first ball — the one at the tip of the triangle — the one closest to the breaker. If it's not touching the other balls, you have a bad rack. Any space between that first ball and the rest of the rack will cause the ball to bounce from the impact of the cue ball into the other balls — meaning, it will hit the two balls directly next to it, then bounce back into the cue ball and then back again at the racked balls. You will not be getting 100 percent power out of your break.
While it's crucial for the head ball to be frozen to (be touching) the others, it's also important that all the balls be frozen to one another. Look over the rack carefully to make sure the other balls are frozen as well.