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