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