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