Tips for the AWA:
1. Organize your thoughts and list your ideas (the noteboards are available during the AWA section)
2. Try to have a template ready for your write-up - this is only possible since you pretty much know the format of the questions (analysis, argument). Documents in legalese are a great source for good formats to analyze an issue or argument.
3. There is no word limit. So, dont constrain yourself unnecessarily but at the same time, dont be verbose - remember that the human reader is a graduate student probably earning less than minimum wage to read your (and a 100 other) write-ups. They wont be too interested in a book.
4. IMHO. including references to real-life events/facts helps your essays (did it both times and got 6.0 on each ocassion). Of course, the references should be appropriate in the context of your essay.
I think the template suggestions in PR's GMAT prep book are decent. The most important thing to remember is that you should use the AWA sections as warm-up for the real thing. Good luck!