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