dust bath plans

I am reading up on mites and things and have learned that it makes a LOT of sense to set up a chicken dust bath and add stuff like DE. But my questions are: 1. How big should the dust bath be? 2. Other than DE should I put anything else in their dust bath to prevent pests and keep it healthy? 3...

Hardwood floors were just added, and that created a lot of sawdust from woodcutting. Is this sawdust safe for quail to dustbath in?

Assume I know nothing about construction. And I have a little pile of 2x4's left over from another job. I don't want them to go to waste. Now I think, what could I do (or more accurately, have done) with these things? Idea! Build a dust bath for my girlies. Can anybody direct me to a simple plan...