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