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