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