|I stole this .GIF from Chelle at Coffee and Zombie Movies.*|
I learned this little gesture in Nicaragua and let me tell you it really works. If you want to say no a little bit more forcefully than usual, for example when you get off a train and people attack you with signs for their hostel, but you already have your hostel booked. Maybe they won't leave you alone.
Or maybe a scary bum is following you trying to get money. You already said no politely. Maybe you need to shake him.
Just wag your finger and Voila! UNIVERSAL SNUB.
*I don't know where she stole it from.