Making a starter is easy. It just takes time, up to a week. All you need is some flour and water, to make a culture medium, and a warm space (like the top of your fridge) to encourage the yeast to make a home and grow in the culture medium. This makes a 100% hydration starter.
You need this everyday for up to a week:
7 tablespoons flour
4 tablespoons water
1. In a jar or container, combine the water and flour. It will make a sticky paste. Cover the container with a towel and set on top of the fridge.
2. Check it in 24 hours. It may or may not have a few bubbles in it, signifying that some yeast have taken a home in your culture. If there are no bubbles, that's okay, just feed the starter again.
3. On day 3, dump out half the culture before feeding. You should have more bubbles today.
4. Keep doing this till day 5 or 7 when you have a strong starter.
5. You know you have a strong starter if: (a) it doubles in size (so full of bubbles) within 6 hours of feeding it and, (b) the starter should float when you place a small dollop (about 1/2 teaspoon) in a glass of water. At this point, it is ready to use to bake bread!