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