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