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