This is a living document where I (Jono) try to get a good working basic sourdough loaf. Its based on a tweaked version of the Tartine country sourdough recipe. It takes about 3 days to make a loaf, but its only 20-30 minutes of active time and its certainly worth the wait.
I am not covering how to make your own starter here. I presume you have a healthy starter already on hand.
I keep about 10g (or a tablespoon) of starter in the fridge. When I'm ready to bake a two loaf recipe I take it out and add 90g water and 80g flour. I mix with a chopstick (dont use a metal utensil - I hear thats bad). Then I put it in my oven on the proof setting. It takes about 2-5 hours to double in size and be ready for use.
Sometimes I feed the left over starter and let it sit on the counter for 1-2 hours before putting it back in the fridge. Sometimes I put it back in the fridge without feeding it.
I have never gone more then 2 weeks without using my starter. If you go longer you might need to feed it longer or multiple times for it to be healthy enough for use.
These are uses for your extra starter if you have too much left over.
Scallion pancakes - https://dusdoughs.com/2020/04/17/sourdough-discard-scallion-pancakes/
Sourdough pancakes - http://allrecipes.com/recipe/sourdough-pancakes/
According to the book makes two loaves, but I often to make three from it.