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