The Tree of Life, kayon, marks the beginning and the end of a Balinese shadow play.
When the dalang (shadow master) is ready to start the shadow play performance, he signals to the gamelan musicians to begin the pamungkah (overture) by knocking softly three times on the wooden puppet box. Then he opens the wooden box and takes the puppets out one by one. One of the first puppets to appear is the tree of life, the Kekayonan (kayon). The dalang holds this figure to his forehead, mutters an invocation, which names the points of the compass, and places the kayon and himself in the center. Then the kayon begins a dance, which reflects the stages of life, from birth to death. It starts low on the screen, fluttering like an insect from side to side, pausing occasionally in time with the music. Little by little, in fits and starts it grows until it fills one side of the screen, then the other. Reaching its apogee it starts to spin slowly. Always moving from side to side, it gradually settles in the center.
The kayon, tree of life, is one of the most versatile and important figures. It’s meaning is often traced to the Sanskirt words for “tree” and “thought.” The puppet is used like a stage curtain to indicate the beginning and end of the performance, scene changes, shifts of location, and passage of time. Depending on how it is used, it can become a tree, a mountain, wind, rain, water, clouds, holy radiance, or a weapon. Once the kayon is placed in the center of the screen, the dalang begins to sort and place the puppets on either side of the kayon.
(Excerpt from the Asian Theatre Journal Article Volume 3, Number 1, Spring 1986, Bima Suraga: A Balinese Shadow Play as Performed by Ida Bagus Ngurah translated and with an introduction by Larry Reed)