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