If you've done any reading, whether on the web or in a book, about Wicca, then you should be familiar with the phrase "book of shadows", and what it means. If you don't, basically, a book of shadows is a book in which you keep all of your magickal workings. So, how do you know what to put in your book of shadows (or BOS)? The answer is really quite simple...put anything you want in it. Everyone's BOS is different, and that is what makes it special. There are, however, a few things are you will most likely see in many BOS's, and that is what I will tell you here.
But, first, what should the book look like? I use a 3-ring binder, as it makes it very easy to add, subtract, or re-order what have in it. Other people prefer books with a 'real' binding, while others (especially neo-pagans) even use a computer disc as their BOS, and print out the rituals before performing them. Your BOS can be any of these, or anything else which works well for you.
Ok, what I do is this. Before I perform a ritual or a spell, whether I wrote it myself or got it from some other source, I write it out and add it to my BOS. If I copied it from somewhere else, I write down where I found it. Your BOS can also be used as a magickal journal. Whenever you perform a ritual or spell for a specific person, for example, to get a job, you should write down how you felt before, during , and after the ritual. If you noticed results, you would want to record that also. This way, if you have a need to do the ritual again, you can see how it worked for you in the past.
You could also use your BOS as a place to 'vent' your feelings. By this I mean just write down who the Goddess is to you, what Wicca is, or how you feel about the world.
Basically, as I stated before, what you put into your BOS is completely up to you...just go wild!