It is exactly like yeast. It just starts to bubble and expand. It produces a slightly sour smell. Adding quantity to the flour to make bread is just trial and error at first, but basically the less you add the longer it takes to rise and therefore it produces greater flavour. Obviously baking stops and kills the little critters!

I tried some of the other methods using grapes or apples but it always ended in tears. I also use to seed the starter with a few grains of yeast but it isn't the same. I still do that (before this starter) if I'm having some pizza in a few days. Starting from scratch with just flour and water and being patient has been really easy. I'm surprised that so much myth has surrounded it.

Obviously I still haven't actually produced a loaf yet, but things are looking pretty good!