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