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