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