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