Mix the equal quantities of flour and water together in the small bowl, getting most of the big lumps out, and transfer it into your glass jar.
Put the lid loosely on and set it aside on your counter. If you prefer, you can use a piece of cotton cloth over the jar instead of the lid - just make sure that the mixture can 'breathe'.
Every day, for the next five days, you will 'feed' this mixture by adding 1/3 cup of water and 1/3 cup flour and mixing it in until smooth. You will begin to notice bubbles in your mixture starting to appear and a slight sour smell. Don't be alarmed - bubbles mean fermentation is occurring, which is what we want. However, there should be no mould or foul smell. If there is, throw the mixture away and begin again. Ensure that your glass jar is thoroughly clean.
After five days, your mixture should be nice and bubbly and ready to use. You have just made your very own starter!