I just googled it and found several different "recipes", all with different measurements of the AP, salt and baking powder. What does everyone here suggest on measurements?
This is what I have as a note on one of my recipes: "For each cup of all-purpose flour, add 1 1/2 teaspoons of baking powder and 1/2 teaspoon of salt." I don't really think you could go too far wrong with any measurement in this neighborhood. I was surprised to learn that many of my Northern and Canadian friends were totally unaware of the existence of self-rising flour. Shoot, we even use self-rising cornmeal mix!