Shave your head 

Coined by the great Gatherqueef, this phrase refers to an old video in which a wife shaving the pubic hair of her husband accidentally cut the head of his penis off.

"Shave your head," as in "cut off the head of your penis off with a vibrating razor or some other overly-sharp thing that it is nearly impossible to do."

Shave your head by Gatherqueef January 13, 2009

I can tell by the shape of your head 

A term used to suggest that someones whole life/personality can be determined merely by their appearance(The shape of their head). This is not alluding to the fact that archeologists actually can determine a lot about someone by the shape of their head; This can be done just by looking at them.

Look at yourself, I can tell by the shape of your head that you are a bitch; everyone can.

I can tell by the shape of your head by xGUNy September 2, 2019

give your head a shake

A phrase which has never actually been spoken aloud. Instead, it is found exclusively in letters to the editor and on message-boards. Must be spoken with a grumpy old white man accent.

Legalize marijuana? You need to give your head a shake, boy. And get off my lawn.

give your head a shake by Pedobar October 27, 2011