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