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