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