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