How to use baking soda and water for acne?

First of all, I want to know how much baking soda you would use for just one face wash, and how much water to put with it. And is the water supposed to be hot, or cold? Also, when all you acne/pimples/zits or whatever are gone, should you continue using the baking soda and water, or can you use any other products? Last question here... does it only get rid of the red marks, or ALL acne/zits/pimples?