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