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