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