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