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