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