Help me see what the following English passage means. You don't need to translate all of them, just tell me how to do it.

The wizard took out 30 grains for divination, then randomly took out some (uncountable), and then divided the pile of grain into four groups. Whether it is auspicious or unlucky depends on two factors. The first is the factor, and the last number of groups is odd or even; The second factor is whether the remaining four tablets are odd or even. If both results are even, it means good luck or optimistic answer; If both results are odd, it means unlucky or the answer is no; If the results are odd and even, the results are unknown.