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