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