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