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