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