Note to Hamlet, 5.1.39: "confess thyself"

First Clown probably means to say, "Confess thyself and be hanged," but the Second Clown interrupts by saying "Go to."

"Confess thyself and be hanged" was a common insult, which had its origin in the fact that before a person was hanged, they were supposed to make a confession of sins to save their souls. Thus a person who is hopeless, clueless, lame, stupid, oblivious, or otherwise worthless can be told that they should "confess thyself and be hanged," because there is absolutely nothing else for them to do.