How do you revise a statement you've submitted to police?

It's hard to say without more information.

What did you do?

Just call the station, tell them you have more information and ask when you can speak to the arresting officer. They'll work it out. Do know that you will be adding a second statement... but nothing will be removed from the first.

You've been arrested? You shouldn't be giving ANY statements to police. You should assert your rights to remain silent and to consult with an attorney. Before you "revise" a statement that was already given, you should consult a competent criminal defense attorney.

Arrested on false accusations
Someone I love was arrested on false accusations of contributing to the delinquency of a juvenile and molestation. However, it was the juvenile who sexually approached the accused. The accused was shocked and did not return sexual advances and police were there directly after it happened. The accused didn't mention that sexual advances were made towards him when he was initially questioned so as to not embarrass the juvenile, and at the time, had no idea the the juvenile had accused him of molestation to the officers. He was arrested and a trial date has been set, but we don't know for sure what the juvenile said to convince the officers. The accused needs to revise his statement to include information on the sexual advances what were made on him by the accuser.

Looking for a good defense attorney
we are also in the process of finding a competent defense attorney in our area. Initial statement has already been made.