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)(13,20)(14,18)(15,23)(16,19)(17,21)(22,25)(24,26) involution — undirected(3,5,6,10)(4,7,8,9)(5,10)(7,9)(11,13,16,22)(12,17,19,26)(14,21,15,24)(18,25,23,20)(4,8)(7,9)(11,12)(13,17)(14,23)(15,18)(16,19)(20,21)(22,26)(24,25) involution — undirected(11,14,16,15)(12,18,19,23)(13,21,22,24)(17,25,26,20)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.