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)(24,25)(28,29)(30,34)(31,36)(32,35) involution — undirected(5,6)(7,13)(8,11)(9,12)(10,15)(14,19)(16,18)(17,20)(21,22,24,34,26,30,25,27)(23,31,35,29,33,28,32,36)(2,4)(5,7,9,15)(6,10,12,13)(8,16,17,14)(11,19,20,18)(21,23,26,33)(22,28,30,31)(24,35,25,32)(27,29,34,36)(5,8,9,17)(6,11,12,20)(7,14,15,16)(10,18,13,19)(21,23)(22,29)(24,32)(25,35)(26,33)(27,28)(30,36)(31,34)(6,12)(10,13)(11,20)(18,19)(21,24,26,25)(22,27,30,34)(23,32,33,35)(28,36,31,29)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.