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