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