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