While talking with your stoned friend face to face, occasionally let your eyes drift over their shoulder as if something odd has caught your eye in the distance. Shake it off, continue doing it a few times and when they finally ask you, just say you thought you saw something but you didn’t. Carry on the conversation for another few minutes as normal, before once again setting your stare beyond them, screaming the loudest curse word you can and running out of the room. Suffice to say, change of underwear required immediately!