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