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