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)(21,22,27,31)(23,28,26,30)(24,34,25,35)(29,32,36,33)(6,9)(10,12)(13,14)(15,18)(16,17)(19,20)(21,23,27,26)(22,28,31,30)(24,32,25,33)(29,34,36,35)(2,4)(5,7)(6,10)(8,11)(9,12)(14,17)(18,20)(21,24,27,25)(22,29,31,36)(23,32,26,33)(28,34,30,35)(7,11)(10,12)(13,15,16,19)(14,18,17,20)(21,25,27,24)(22,29,31,36)(23,33,26,32)(28,34,30,35)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.