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