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