In NLP they say that your mind is an amazing computer that will answer any question you ask of it, you just have to know how and what to ask.
Opening and closing affirmations are pretty easy to understand. Just use the ones that are in the book and if you want, make up unique ones that get you interested in what you might read. Obviously no one can tell you how to do this.
Read page 57 of the 3rd edition book about "Probe your Mind." I think it's the most important step in the system and if you don't do it exactly the way that page says to do it, I don't think PR will even work at all for you.
The book says that the more curious you are about what you want and the more you desire the information you want, the better. So if you HAVE to get a report done, there's your desire right there, the desire to get it done. If you're curious about a topic anyway then the info will come to you easily. If you're reading without the sense of curiosity or desire but just out of boredom, your results will be probably not that great, or at least that's been my experience.
If you run thru the PR steps without really awakening your mind then you're results are going to suck.
I wouldn't worry about falling asleep. Heck, that's half the reason I PR late at night.