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