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