It is so easy, really. I searched the internet expecting to find complicated directions or a long drawn out list of conditions that needed to be met to make it work.
What I found was that sourdough starter is the easiest and most basic of ways to make your own leavening agent for many things, not just bread. But before you can make any of these "things" you have to make the starter.
All you need is flour, water, a non-reactive bowl and a non-reactive spoon. That's it, really. You can add a little honey to help speed up the fermenting if you want as the wild yeast loves the glucose.
Simply put equal parts of flour and water into your bowl and stir it very well. I found I could not get all the lumps out. That's OK, they will disappear with time. Now just let your bowl sit out uncovered until it starts to get bubbly and smells a bit...um...well...sour. That's it, you just made sourdough starter.
Some people like to put a little commercial bread yeast in to get things started. You can do that if you wish. Just remember that your sourdough starter will then be a product of that commercial yeast, and not the wild yeasts that naturally occur in your area. Personally, I like the idea of grabbing from my environment what is right there just waiting for me to harness it.
Another thing I have read everywhere is that when you feed your starter, you take out "x" amount of starter and replace it with "x" amount of water/flour mixture. Me, I just add flour and water. Then when I take it out to use it, I find I don't have to wait so long for it to be ready to use because I have more starter. For example, if I start with two cups of starter and then feed it by taking out one cup of starter then add in 1/2 cup of water and 1/2 cup flour, I still only have two cups of starter. When I want to make bread, I then have to take out my starter, add a cup of water and a cup of flour and wait overnight for it to "sponge" so I can use two cups for my bread. But if I just add when I feed rather than take out, I only need to remove the starter I need for my recipe and allow it to come to room temperature. (Did I forget to mention you store your starter in the fridge after it ferments?) I just store mine in an old Mason Jar.
So there are the basics. Now who is ready to make their first sourdough starter? Or who in the Hersey, MI area wants some of mine? I have extra.