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