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