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