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