I am a victim of abuse and currently going through the VAWA process.
My experience is detailed on my post #12 in this thread here: http://www.visajourney.com/forums/index.php?showtopic=121135
My attorney has asked that i provide at least one affidavit from a witness (i have two, the friend i moved in with and my brother).
But they have no idea how to write one, nor what format, me neither.
Does anyone know how? Can anyone provide me with a sample format or draft, where they can just plug in what they witnessed?
Please help.

There isn't any said format. The witnesses should simply document their knowledge of the abusive relationship that you had with your petitioner. Why not ask your attorney for guidance?

My thoughts exactly. A starting place would be for them to simply write a letter telling what they observed. They can write it the same way they would tell a friend about it but just address it to, "To whom it may concern:" and have a Notary witness their signature. Your attorney may have a better idea.

Information in the letter should be detailed as possible with regards to dates and time.

See the notary for a proper format, but usually begins with " I JOHN SMITH state the following.....etc."

At the end, they must say "I declare under the penalty of perjury..."