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