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