It will get your mind wrapped up in the story if you stop halfway through. It's best to read poems or short stories.
If you try really hard to fall asleep, you won't because you are concentrating too hard. Instead clear your mind and think of happy thoughts.
For two reasons think of nice things:
1. It's easier to fall asleep with happy thoughts instead of bad ones churning through your head.
Disclaimer: The tips in this post are not mine. I did not pass them off as my own nor did I ever intend to do so. I give all credit where credit is due to Saffron Lallem and in by doing so I have a total of 4 links back to her blog post and her google+ account. I posted her tips with her permission. The picture is from the Facebook. The owner is unknown.