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