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