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