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