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