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