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