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