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