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