The documents required for O-2 visa are:
the filled Form DS-156,
a 2×2 inch photograph,
a valid passport,
proof that you will return to your home country,
an official agreement between you and the petitioner detailing the terms and conditions of the services,
proof of you and the O-1 Visa holders’ professional relationship, and roof that you are capable of assisting the O-1 visa holder!
