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)(21,22,26,27)(23,30,33,28)(24,29,25,35)(31,34,36,32)(5,7)(6,11)(8,15)(9,18)(10,16)(12,19)(13,14)(17,20)(21,23)(22,28)(24,34)(25,32)(26,33)(27,30)(29,31)(35,36) involution — undirected(2,4)(21,24,26,25)(22,29,27,35)(23,31,33,36)(28,32,30,34)(5,8,10,9)(6,12,13,17)(7,15,16,18)(11,19,14,20)(21,25,26,24)(22,29,27,35)(23,32,33,34)(28,31,30,36)(5,9,10,8)(6,12,13,17)(7,15,16,18)(11,20,14,19)(22,27)(23,28)(29,35)(30,33)(31,32)(34,36)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.