Practice to Balance Heaven and Earth from Book

For L4P7, we contemplated the meaning of the line positions of Heaven (Chyan) with 6 unbroken lines, representing full yang, and Earth (Kun) with 6 broken lines, representing full yin. It just so happened (likely NOT coincidence) that I read during that month of the pillar from one of Om Ni's books about a practice related to visualizing and balancing these energies. 


One traces and visualizes the symbol for Chyan (or the 6 unbroken lines) on the left hand and Kun (or the 6 broken lines) on the right hand. Then the hands are rubbed together and shaken. But of course, I forgot to immediately write down the book reference for this practice. 


Do you know which book has this practice? 


I would like to create a meditation that combines both the physical aspect of using the hands with the contemplative aspect of the meaning. 


I personally have started trying to use the hand practice as a way to gain perspective at potential time of over-reaction. Your help is appreciated.