Step by step
Add yeast to the dough and stir in well, then add the oil and mix again. Then add salt and knead in the food mixer for 5 more minutes.
Tips
You absolutely must not make a mistake when choosing the main ingredient to prepare your starter dough: make sure you buy a flour with strength value above 300.
Trivia
The definition of this starter dough is a dough made from water, flour and yeast with a rising that lasts at least 16 hours.