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