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