Doubt in reading comprehension strategy

I am facing issues while selecting strategy to solve long passage. My problem is I am taking too much time while solving long passage. I am confused with using sentence function or scanning or paragraph idea. Its seems like it is not working for me. I continuously have to go back to the passage.
Now I am thinking of fresh start for long passage.
Can you suggest me for long passage which strategy should I start with and slowly incorporate other strategy(If possible can you mention in sequence)??
Thank you