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