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