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