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