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