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