1. The sign cannot be placed the open.
2. You can never hide a Punch to the Face sign in the same place as before.
3. You can never hide a Punch to the Face sign where someone else has hidden one.
4. You cannot force someone or trick someone into seeing a sign.
5. No lame spots
The Punch to the Face can be any size and be made in anyway you can imagine. The more creative the better.
Should you be a victim of a truly epic Punch to the Face sign, you must shout to the heavens in anguish as though God himself has punched you in the Face.
Joe grabs Jim's phone while Jim is not looking. He quickly takes a picture of his fist and makes it the background. He then types a banner that says "Punch to the Face" and places the phone back down. Hours later Jim picks up the phone only to be punched in the face. Jim reacts horribly and vows revenge.