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