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