Whenever you describe something by comparing it with something else, you are using figurative language. 

Simile

A simile uses the words “like” or “as” to compare one object or idea with another to suggest they are alike.
Example: busy as a bee

Metaphor

The metaphor states a fact or draws a verbal picture by the use of comparison. A simile would say you are like something; a metaphor is more positive - it says you are something. 
Example: You are what you eat.

Personification  

A figure of speech in which human characteristics are given to an animal or an object. 
Example: My teddy bear gave me a hug.

Alliteration

The repetition of the same initial letter, sound, or group of sounds in a series of words. Alliteration includes tongue twisters. 
Example: She sells seashells by the seashore.

Onomatopoeia

The use of a word to describe or imitate a natural sound or the sound made by an object or an action. 
Example: snap crackle pop 

Hyperbole

An exaggeration that is so dramatic that no one would believe the statement is true. Tall tales are hyperboles.
Example: He was so hungry, he ate that whole cornfield for lunch, stalks and all.

Idioms

According to Webster's Dictionary, an idiom is defined as: peculiar to itself either grammatically (as no, it wasn't me) or in having a meaning that cannot be derived from the conjoined meanings of its elements. 
Example: Monday week for "the Monday a week after next Monday"

Clichés 

A cliché is an expression that has been used so often that it has become trite and sometimes boring. 
Example: Many hands make light work.