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