The 8 Trigrams of the I Ching, the ancient Chinese divinatory text based on the teachings of Taoism, are formed by the throwing of three coins. Heads is counted as 3, Tails as 2. If the sum is even, draw a broken, or Yin line. If odd, draw an unbroken, or Yang line. Do this three times, starting with the bottom line (all the trigrams above have their base towards the centre of the wheel).