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