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