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