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