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