In small bowl, combine yeast and warm water (temperature is very important). Proof yeast 10 minutes.
In separate bowl, combine flour and sugar, stir in milk. Blend well. Add yeast to mixture.
Measure out 1 cup batter into each of two Ziploc bags. This is Day 1 of the 10 day baking cycle. Keep one starter for yourself, and give the other to a friend along with instructions for the 10 day baking cycle.