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