There is nothing like warm toasted sourdough bread smeared with real butter and shared with friends over an afternoon meal. Everyone has their own version of how to create the starter, here's mine;
1 C warm water
1 C flour
put in glass jar and let sit on the counter over night
every 24 hours feed it
1/2 C water & 1/2 C flour
for 3 or 4 days
It'll be bubbly and have a pleasant yeasty smell when it's ready.
You can keep it on the counter and feed it everyday or put it in the fridge to slow down the growth and feed it one a week.
The picture above is a good example of the bubbles and texture, sorry about the dark kitchen shadows, the dough is really make from wheat and is beige in color.