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