The article by Carol Saller does a great job of introducing the basics. Although I've been dealing with such redlines for many years, the article a few tips that I found useful. So whether you're new at the game or a seasoned author, I recommend:
Deciphering a Redlined ManuscriptTip: You can follow Lingua Franca, a blog about language and writing in academe, by clicking the "subscribe" link at the bottom of the right column next to any article in the blog.
Lingua Franca (The Chronicle of Higher Education). 16 Jan 2012. Accessed 17 Jan 2012.