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