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