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