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