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