2 1/4 teaspoons yeast in a jar = 1 packet of Active Dry Yeast.
There are different kinds of yeast, make sure you have the correct one your recipe calls for.
When using yeast in a jar from fridge, measure the amount you need and allow it to get to room temperature before adding it to your recipe.
A thermometer for cooking is very helpful to have on hand, especially when getting the correct temperature water so you don't kill the yeast. When dissolving yeast directly in the water before adding it to the flour mixture I have seen the water temperature needs to be between 105-115 degrees(F). If you add the yeast to the direct flour mixture and then add a water mixture to that, I have seen the water needs to be between 120-130 degrees(F). (This is for the Active Dry Yeast blend).
The bread dough needs to rise in a warm place away from any draft. I use the inside of my warmed up microwave (30 seconds), which I warm up before putting my gigantic bowl of bread dough into it. I have also heard of people using the inside of their warmed oven to do this.
A rolling pin is great when getting the gas bubbles out before forming the loaf to allow it to rise a second time. I personally use a french rolling pin because the tapered edges are easier for me to use.
I hope some of the input will help some of you bakers out there. I bake my bread by hand and do not use a bread machine, I do not know if the same rules apply to yeast when using the bread machine, but I can only imagine they are similar if they aren't the same. For those of you new bakers out there, don't give up on the yeast, it's tricky but I promise that with enough trial and error you will learn how to work with it.