Things You'll Need
Measuring cup or small bowl
Milk or water
Dry active yeast
Home bread bakers have a number of options when it comes to yeast. The refrigerator section at the supermarket will have small blocks of fresh yeast, the same kind most professional bread bakers use. This is live, perishable yeast and needs only to be crumbled into wet ingredients. Quick-rising or bread machine yeast, which comes in the form of dry grains, can be sprinkled directly into the dry ingredients. Dry active yeast, the most common form in home kitchens, must be softened in warm milk or water before it is added to dough.
Fill a measuring cup or small bowl with warm water or milk, as directed in the recipe. Most recipes will instruct you to dissolve a small amount of sugar in the warm liquid, as well. The ideal temperature for the liquid is 100 to 110 degrees F, just a little above body temperature.
Open your package of active dry yeast and sprinkle it evenly over the surface of the milk or water.
Wait 10 minutes, then check the yeast. By this time it should have formed a thick layer of froth on top of the liquid, and have a distinctly yeasty smell. If it hasn't done so, the yeast is too old to be viable and should be discarded.
Add the softened yeast to the rest of the ingredients, as directed in the recipe.