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