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