The Book of Shadows (BOS) is used to store information you'll need in your magical tradition. Many Pagans and Wiccans feel a BOS should be handwritten, but some use a computer to store information as well. Bear in mind that a BOS is considered a sacred tool, which means it is an item of power that should be consecrated with all of your other magical tools. Copy spells and rituals into your BOS by hand - this will not only transfer energy to the writer, but it also helps you to memorize the contents. Make sure you write legibly enough that you'll be able to read your notes during a ritual!