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