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