One vertex per element, one color per generator, with an edge from x to x·s.
(6,9)(10,11)(13,14)(15,19)(16,18)(17,20)(21,22)(23,26)(24,27)(25,29)(28,32)(30,33)(31,35)(34,36) involution — undirected(1,2)(3,4)(5,6,8,9)(7,11,12,10)(13,15)(14,17)(16,20)(18,19)(2,4)(14,18)(17,19)(21,23,25,31)(22,26,29,35)(24,30,32,36)(27,33,28,34)(5,7,8,12)(6,10,9,11)(15,20)(17,19)(22,27)(24,32)(26,33)(28,29)(30,36)(34,35)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.