Since you are asking specifically about improving reading skill, I think Tsumego is the obvious choice. There are many ways to improve, but reading ability in general is trained the quickest with Tsumego. And since nobody has mentioned how to do it yet, there is definitely a proper way to do Tsumego. A wonderful treatment of that topic can be found in the free Go book, 81 Little Lions: An Introduction to the 9x9 Board for Advanced Beginners, by Immanuel deVillers, page 20.
There are a lot of articles on the topic of improvement and for reading at Sensei’s Library. Just do a search for either term and you will see a lot of related articles.