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