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