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