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