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