One vertex per element, one color per generator, with an edge from x to x·s.
(5,6)(7,13)(8,12)(9,11)(10,15)(14,20)(16,18)(17,19)(22,27)(23,30)(24,26)(28,35)(31,32)(34,36) involution — undirected(1,2)(3,4)(5,7,9,15)(6,10,11,13)(8,16,17,14)(12,20,19,18)(21,22,25,27)(23,28,32,34)(24,33,26,29)(30,36,31,35)(2,4)(21,23,26,30,25,32,24,31)(22,28,29,36,27,34,33,35)(6,11)(10,13)(12,19)(18,20)(21,24,25,26)(22,29,27,33)(23,31,32,30)(28,36,34,35)(2,4)(5,8,9,17)(6,12,11,19)(7,14,15,16)(10,18,13,20)(22,27)(28,34)(29,33)(35,36)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.