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