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