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