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