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