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