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