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