What is a one-sentence summary of the following article?
Before you begin your foray into home brewing, get a notebook, and note down everything you do—the cleaning process, what strain of yeast, the amount and specific type of malt, what variety of hops, and any specialty grains or other ingredients used to produce your beer. This will allow you to reproduce any given brew, or provide a basis for experimentation and improvement.

Summary:
Take notes.