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