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