If we agree on joint legal decision making what paperwork do we need to complete?

You will need a parenting plan, signed by both parents that includes:
•    A designation of the legal decision making as joint or sole as defined in A.R.S. § 25-401.
•    The rights and responsibilities of each parent for the personal care of the child and for decisions in areas such as education, health care and religious training.
•    A practical schedule of parenting time for the child, including holidays and school vacations.
•    A procedure for the exchanges of the child, including location and responsibility for transportation.
•    A procedure by which proposed changes, disputes and alleged breaches may be mediated or resolved, which may include the use of conciliation services or private counseling.
•    A procedure for periodic review of the terms of the plan by the parents.
•    A procedure for communicating with each other about the child, including methods and frequency.
•    A statement that each party has read, understands and will abide by the notification requirements of A.R.S. § 25-403.05, subsection B.