How did Shang Dynasty use Oracle Bone Inscriptions for divination?

Oracle Bone Inscriptions's divination method is to drill a hole in the back of the processed tortoise shell or animal bone, drill it to the place that is about to penetrate but not yet penetrated, and then bake it with fire. Cracks will appear around the drilled hole in the front of the tortoise shell. These lines are called "signs". The person in charge of observing the grains, that is, the person in charge of divination, is called the "diviner". After judging good and bad, the content of divination is written and portrayed on Oracle bones.