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