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)(15,16)(19,20)(21,22,26,29)(23,30,24,27)(25,33,34,28)(31,35,32,36)(6,10)(8,11)(14,18)(19,20)(21,23,26,24)(22,27,29,30)(25,31,34,32)(28,35,33,36)(5,7)(6,11)(8,10)(9,12)(13,14)(15,19)(16,20)(17,18)(21,24,26,23)(22,27,29,30)(25,32,34,31)(28,35,33,36)(1,2)(3,4)(5,7)(6,8)(9,12)(10,11)(13,15,17,16)(14,19,18,20)(21,22)(23,27)(24,30)(25,33)(26,29)(28,34)(31,36)(32,35)(5,8)(6,12)(7,10)(9,11)(13,16,17,15)(14,20,18,19)(21,25,26,34)(22,28,29,33)(23,31,24,32)(27,35,30,36)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.