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