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