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