Here are useful tips in writing:
There are plenty of folks happy to tell you how to write better, just as
any doctor will tell you to “eat right and exercise.” But changing your
writing (or eating) habits only happens when you understand why you do what you do. I can help you with that.
I also came across with this article: https://writingtips.wordpress.com/2014/07/25/double-possessive-revisited/