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