Summarize this article in one sentence.
There are tons of notebooks and journals to choose from. Pick one that you like and decorate it in any way you'd like.  Decorative ideas include: A saying from the Bible, scrapbook cutouts, your name in large letters, words that represent the joy of Christianity to you, etc. If you'd rather, you can even make a journal from scratch. It all depends on how craft-savvy you are. There are prayer journal templates available for printing off from a variety of online sites; just do a quick search and choose what you like the look of. This will help to guide you with the purpose for the journal and will help anyone else you'd like to read it to see what you were aiming to achieve through the journal. You don't have to share it with anyone though, but it can be nice to hand down this journal as a family heirloom later.

Summary:
Get a good journal or notebook. Make a front page explaining what you're doing.