The I Ching is traditionally performed by the casting of yarrow stalks (or sticks) or coins, generating a hexagram which is composed of the two stacks of three lines within it, called the trigrams. The meanings of the hexagrams are connected to those of the trigrams that make them up, and their symbolism is ultimately based on seeing solid lines as strong and active (Yang), and broken lines as weak and passive (Ying). There are eight trigrams and each of them has a metaphorical meaning based on its composition of solid and broken lines.

The concept of the old or changing lines is derived from the theory of Yin and Yang, as seen in the Taoist saying: the Way of the Tao is Return. When the old Yin or Yang reach their extremes, they actually change into their opposite forces, thus the old Yin becomes Yang and so forth. These old or changing lines create a second hexagram, signifying the future situation, after the change has occurred. Aside from the symbolism of each hexagram, the text of the I Ching also provides the special meanings attached to these changing lines, therefore the sum of answers one is able to derive from the I Ching culminates to 4,096.

In preparation for a reading, there are a few traditional measures that may be observed such as washing your hands, lighting incense and facing south.

Methods:
The Yarrow Sticks Method
The Coin Method
The Computer Method