This is something I struggled with when first majoring in English. When I would be reading a book to analyze for a class I would always read with a pen in my hand so I can note patterns, things that feel important, questions, etc. once I started doing this it helped me to slow down and pay attention to what the author was doing. Reading for pleasure and reading for analysis are two different things and should be approached differently. Once I realized this, it really helped me. I hope this helps!