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