How do you write a monologue?

Question:

How do you write a monologue?

I need all the facts

Best Answer - Chosen by Asker: You start talking to yourself and write it down.
or You mentally put yourself into the person who is speaking and write down what they are saying.
When a play for several characters is written, the writer must see the play going on and play all the characters in the mind's eye, shifting between characters with each step of the dialog.
The same thing in a monologue, except the transitions are changes of tone or thru line of thought