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