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)(15,16)(17,23)(18,22)(19,24)(20,25)(21,27)(26,28)(5,6)(7,11)(8,10)(9,12)(13,15,17,28,19,21,18,25)(14,20,22,27,24,26,23,16)(2,4)(5,7)(6,9)(8,12)(10,11)(13,16)(14,21)(15,24)(17,20)(18,26)(19,27)(22,25)(23,28) involution — undirected(7,12)(9,11)(13,15)(14,16)(17,25)(18,28)(19,21)(20,23)(22,26)(24,27) involution — undirected(6,10)(9,11)(13,17,19,18)(14,22,24,23)(15,25,21,28)(16,26,27,20)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.