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