A Leopard Can't Change His Spots

It's not allowed.

Brownie Points

You eat it.

Chip on his Shoulder

You look at the shoulders.

Dirt Poor

 You have no money.

Eat Drink and Be Merry

 I will drink your hair before getting merried.

Funny Farm

 Laugh forever.

Go The Extra Mile

 Go away.

Hit the Hay

Take a break. 

I'll Have His Head On A Platter

 Cut the head with the platter off.

Joshing Me

 Your bosing someone.

Knock on wood

You hit wood.

Like a chicken with its head cut off

 The chicken was killed.

My Brother's Keeper

No Room to Swing a Cat

It's messy.

Over the Top

 Your on the lead.

Put on your thinking cap

You think.

Quality Time

Your late for something.

Rain Cats and Dogs

Skin of your teeth

 Your very mad.

Til the cows come home

 You come home.

Under the Weather

Van Gogh's ear for music

Who Let The Cat Out Of The Bag 

 Why did you do that?

X marks the spot

You are what you eat

 Your something.

Zero Tolerance

 You are number zero.