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