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