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