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