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)(21,22,25,29)(23,30,33,36)(24,28,26,34)(27,35,31,32)(1,2)(3,4)(5,7)(6,11)(8,15)(9,18)(10,16)(12,19)(13,14)(17,20)(21,22)(23,31)(24,34)(25,29)(26,28)(27,33)(30,35)(32,36) involution — undirected(2,4)(21,23,25,33)(22,27,29,31)(24,32,26,35)(28,36,34,30)(5,8,10,9)(6,12,13,17)(7,15,16,18)(11,19,14,20)(21,22)(23,27)(24,34)(25,29)(26,28)(30,32)(31,33)(35,36)(2,4)(5,9,10,8)(6,12,13,17)(7,15,16,18)(11,20,14,19)(21,24,25,26)(22,28,29,34)(23,32,33,35)(27,36,31,30)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.