Coarse grind, about 6 oz volume of coffee grinds per 32 oz of water. Mix it a little with a wooden spoon, or for lazy like me pour in a little water, add the grinds, then finish filling with water.
Let it sit in a carafe 12 hours, covered with saran wrap, on the kitchen counter.
Filter the resulting liquid, into a second container. Slowly pouring it
through a paper filter in a drip coffee maker would work fine.
The resulting liquid can be stored in the fridge up to 2 weeks. It will be low acid, high flavor. Cut it with 1 part water to one or two parts of the coffee extract.
It makes a great hot coffee (microwave the coffee + water for a couple minutes to heat it), or iced coffee.
A normal store "breakfast blend". coarse ground, works well.
(I can send some coarse next time if you would like to try it.)