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