The best way to activate yeast is to dissolve it in water that is between 105-115 degrees fahrenheit. You should also add a little sugar to the water, which will help to feed the yeast and help it to grow. Once the yeast is dissolved, you can add it to your dough or recipe.there are a few different ways to activate yeast, depending on what you are using it for. If you are making bread, the best way to activate yeast is to add it to warm water with a little sugar and let it sit for a few minutes until it starts to foam. If you are making beer, you will want to add the yeast to the wort (sugary water that the beer is made from) and let it ferment for a few days.