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