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