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