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