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