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