I usually re-read his pocket size statements or observations twice. But in the long run, I think it's good to read him straight through, and not worry about getting 'it' on the first try. He's a philosopher where it's best to meditate on his words and the meaning of his sentences through your own dear time. "The limitlessness of the visual field is clearest when we are seeing nothing in complete darkness." That statement stays in my mind the most because I find myself writing in a state of mind that is very much a dark void. I then fill that space with words, that is usually connected to something visual or a sensuality of an object of some sort.
Wittgenstein didn't write a lot. Some of his 'literature' is from his lectures in class. I'm presuming that this book is him working through his philosophy/thoughts. Which is another reason why I love Wittgenstein's work so much is that it's not about the answer, but the journey. He focuses on the senses, and how that communicate to our brain. His writing is not scientific, but almost poetry. In fact, I tend to look at him as a poet than anything else.