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