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