| Hand signals are used to reference drugs in situations where mentioning them out loud would be a Bad Idea. For instance, when you're sitting in a Denny's booth right behind four cops having breakfast, and you need to tell friend A that friend B is tripping. Or when you're in mixed company (ie, among straight people, your relatives, etc.), but are trying to score something nice to take later in the evening. These are pretty universally known, and even if the recipient doesn't know, none of them are terribly difficult to figure out.
Acid: Slowly place the tip of your index finger on the end of your tongue. This comes from the action of taking a paper blotter hit.
Alcohol: Make a fist with your thumb sticking out. Hold it horizontally, and put the tip of your thumb against your lips. Tilt your head and hand backwards, as if you are gulping from a bottle.
Coke: Rub your straightened, horizontal index finger under your nose while making a sniffing sound. Alternately, rub the pad of your index finger on upper gums and teeth.
Ecstasy: Hold your hand out flat, palm down, thumb in. Move it forward in sort of a sine wave. Signifies "rolling," I think.
Heroin: Hold your arm out, with your elbow at a 90° angle, and your wrist and palm up. Make a fist (still pointing up), and thwack your inner elbow with the index and middle finger of your other hand, like you're trying to find a vein.
Lighter: Make a loose fist with your thumb sticking out. Move your thumb in a striking motion a few times.
Marijuana: Pinch your thumb and index finger together, as though you're holding on to something very small. Purse your lips (like you're going to kiss something) and put the two fingers up against them. Sucking sound optional.
Rolling Papers: Point the thumb, index, and middle finger of both hands at each other, and turn your wrists in unison. This is supposed to look like rolling a sheet of paper into a tube.
| 
