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