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