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