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