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