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