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