I researched on the internet to find the easy steps to follow.
HOW TO MAKE YOUR OWN SOURDOUGH STARTER: THE PATH TO GREAT BREAD
Have you ever wondered how to make your own sourdough starter? Whether it conjures up a crusty, flavorful loaf of bread or a bubbling crock of flour/water starter, sourdough is a treasured part of many bakers’ kitchens. But where does the path to sourdough bread begin? And how do you start? Start in your own home kitchen. And begin by learning how to make your own sourdough starter.
First, a word of advice. Sourdough baking is as much art as science. A sourdough starter includes five key ingredients: flour, water, time, patience, and love.
The following timeline assumes you can find a relatively warm place (68°F to 70°F) to grow your starter. More on that below.
How to make your own sourdough starter via @kingarthurflour
How to make your own sourdough starter, day 1
Combine 4 ounces (1 cup) whole rye flour (pumpernickel) or whole wheat flour with 4 ounces (1/2 cup) non-chlorinated cool water in a non-reactive container. Glass, crockery, stainless steel, or food-grade plastic all work fine for this.
Note that whole grain flour (whole wheat or rye) is used at the beginning of the process. This is because whole grains contain more nutrients and sourdough-friendly microorganisms than all-purpose flour.
You also may have better results if you feed your starter with non-chlorinated cool water; from now on, we’ll refer to this simply as “water.”
Stir everything together thoroughly; make sure there’s no dry flour anywhere. Cover the container loosely and let the mixture sit at warm room temperature (about 70°F) for 24 hours.
A note about room temperature: the colder the environment, the more slowly your starter will grow. If the normal temperature in your home is below 68°F, we suggest finding a smaller, warmer spot to develop your starter. Here are the pictures, and step one through 7.