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