Making a sourdough starter is among the easiest things in the world. The only challenging part is being able to repeat a two minute action regularly throughout a period of ten days. It has been too difficult for me at times, and thus I have tried and failed several times. I have even tried, succeeded, forgot all about it and had to throw it away. The solution has been to make it as easy as possible, the sourdough is consequently used often, often fed, and never stored away for too long.
What you need – Well, to start, what you need is a container, flour, and water. Simple, yes, but let’s make it a little more difficult (or actually easier for you to succeed). You should find a container that holds about a cup, or a wee bit more, and a lid for said contained. I saw fancy glasses and detailed boxes when other people presented their sourdoughs online, screw that! You need something that’s easy to clean and preferably goes in the dishwasher, and to make it even easier, have two. I use some simple boxes from Ikea. Simple boxes with a press-on lid. Then the flour. For white bread you want wheat, for dark bread you want rye, but don’t mix the two. The flour should be organic and wholegrain (I prefer the finely ground). The reason for this is the pesticides and stuff used on most store-bought flour, which could kill the yeast-spores, or at least mess them up.
Hygiene – I’ve seen people using gloves, sterilising their utensils, and making tents for their sourdough containers to avoid bacterias and germs. Trust me, it’s not necessary! The containers must be clean – hot water and soap will do the trick. As for the utensils you use. And, obviously, you must wash your hands (like you always do when working with food. Common sense will also tell you not to sneeze into the flour (or sourdough), don’t use it anymore if you drop it on the floor, and don’t lick you fingers before you touch the dough. I know you know this, but now I’ve said it.
Procedure – First day you take about half a cup of water (I don’t necessarily mean the measurement type of cup, just any normal cup) and enough flour to create a soggy and sticky lump of dough. Leave it on the counter for a day (24+ hours). The next day you remove half the dough (put it in the fridge and use for baking when you need it) and add a fourth of a cup of water and enough dough to get the same icky substance you had the day before. Continue like this until you see the dough coming alive. (If it starts talking you’ve taken it too far) If the texture changes (Wheat becomes very sticky and will, even if made into quite a dry lump of dough, become quite runny. Rye will rise more and be more sponge-like) or it rises, or bubbles appear, you have signs of life. This will take between 2 to 5 days. When it has come alive make it more efficient by feeding it twice a day for 4-5 days.
And please do ask if you have any questions!