Here is a method called SQ4R (SQRRRR) that can help you improve your reading skills :
Survey > Question > Read > Recite > Review > Reflect
Before you read a test, survey it to get its main idea or purpose. Look at the title and subtitles, pictures and their captions, charts and graphs, introduction and conclusion, introductory and concluding sentences.
While you are surveying, ask any question you think the text will answer. You can write these questions to concentrate and focus your attention.
Read each paragraph or section of the text with your questions in mind. Look for the answers, and write them in your own words to guarantee a better understanding.
After you have read and answered all of your questions, remember them, and see if you can answer without going back to the text.
Once you have finished all the text, review your notes (questions and answers) and build a mental organization of the ideas in the text.
Re-read your questions and notes and evaluate how much information you can recall. Try to explain the process you went through and think of how you can improve your reading comprehension.