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