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