If you have never worked with yeast before, don't despair! It is not as difficult as you may have been led to believe. All it takes is understanding a few basic points . . .
Yeast is a living organism. "What? There are living organisms in my bread?" Well, actually not. By the time you get around to spreading the butter, there are dead organisms in your bread. That may seem rather disgusting, but take a moment and think. There are organisms all over your body. There are live, beneficial organisms in your digestive tract. If you eat yogurt, you can replace some of those organisms, which is why people recommend that those who have finished a course of anti-biotics eat yogurt. There are probably dead organisms in a good deal of your food, which is why we are told to cook certain meats until well-done or to heat pre-made food to 160 degrees Fahrenheit. (The temperature at which most microbes die.) At any rate, yeast is an organism.
Yeast can die if not handled properly. As is true for all living organisms, yeast requires certain conditions in which to thrive. If yeast is kept at room temperature for a long time, for instance, it will eventually die, which is why yeast containers have expiration dates. A good way to store yeast if you doubt you will be using it all before the expiration date is in the freezer. Believe it or not, it will not hurt the yeast, and in this way, it stores almost indefinitely. (At least, I've stored yeast in the freezer on the order of years and had it work perfectly fine when I needed it.)
Success in bread recipes with yeast is all about temperature. When you dissolve your yeast in the course of the recipe, pay special attention to the temperature of the water. If the water you use is too hot, it will kill your yeast prematurely and your bread will not rise. On the other hand, if the water is too cold, it will rise, but it will take a very long time as the heat in the room finally heats up the bread dough to the temperature at which the yeast is happy. (Long, cool rising is actually used in some recipes, but even then, the yeast is usually not dissolved in cold water. Incidentally, it's difficult to get the yeast to dissolve in cold water, at all.) The water should be lukewarm, just a touch over your body temperature, roughly 110 degrees Fahrenheit. If you take a dry finger and put it in the water, it should feel ever-so-slightly warm. If you are in doubt, get a thermometer and check until you "get the feel" of the temperature range. Don't worry--it's not really precision rocket science. In all my years of baking bread, I have only killed my yeast once.
If you remember these ideas, you can have every confidence in your ability to work with yeast in baking. Good luck!
