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)(11,12,15,18,16,19,26,17)(13,14,20,23,22,25,21,24)(3,5)(4,8)(6,9)(7,10)(11,13)(12,14)(15,20)(16,22)(17,24)(18,23)(19,25)(21,26) involution — undirected(3,6,7,8)(4,5,9,10)(12,17)(13,20)(15,26)(18,19)(21,22)(23,24)(4,9)(5,10)(11,14)(12,13)(15,24)(16,25)(17,20)(18,21)(19,22)(23,26) 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.