-A spiral note book, a binder, or a computer. Anything that has pages that can store information.
-Writing utensil(s)
Now for the How-to Part. :D
First, you'll want to decide what the heck you want to use. I use a decorative notebook/ diary, but a spiral note book or a binder ,like Akasha0wolf (who has a video on it) suggests, would be just fine. You can go the appealing route and but a cool notebook with even the pages decorated. A folder with brads would be great also! You could even go with a more technological approach by using a Word Processor on a computer.
Alright, now that we have our Book, now we have to put something in it! You could put literally anything in it. If you like a certain article, write it down. If the work is NOT your own, be sure to credit whoever had written the article, spell, etc. I think it's fun to write in different colored inks, or just whatever is available. You could use a fountain pen for a nice cursive. Be sure to date your spells and articles so you don't lose track of when it was created. Also be sure to write down your studies, results, etc. It's like a magick portfolio.
Now for the Computer Stuff.
If you have terrible hand writing, or just want everything to be nice and neat, you could try making a book of shadows on your computer! I don't use this method, but you may find it helpful. Begin by starting up your computer, and open up a Simple word processing software (Word, Microsoft Works, Microsoft Word, AppleWorks, Word Pad, Notepad, etc.) Now type in an intro page if you like example: My Book of Shadows. Then go to the next page, date it and put a topic at the top. Type all of your information, etc. Make a new folder to save your files in Example: Book of Shadows. Then, save all of your information into that folder. Each time you find something new, date it, type, and save.
Thanks to All who read this. Blessed Be, HystericSoul .