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