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