First, throw out most of the Auralex.
Second - Actually make it first, so you know why you're throwing out most of the Auralex - Start reading books by F. Alton Everest. The "Master Handbook of Acoustics" is a must, and there's a book with a title similar to "Building a Recording Studio on a Budget" or something very similar.
Both should be read and generally understood before driving the first nail.
More accurately, both should be read and generally understood before even working out of a bedroom...