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