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