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