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