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