Paperwork

In a perfect world, we wouldn't need this stuff...

A simple generic letter of agreement (contract)
A statement of work, expenses/budget, and compensation.

Contract Addendum - for all the boilerplate stuff
Default releases, copyright assignments, safety, ownership, use, etc. can go here.

Disclaimers: The material contained on this site is for informational purposes and and is NOT presented as any form of legal advice. It is always a good idea to consult your attorney before executing any contract.