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