Every subject has a its own reading protocol. Read the excellent article given below which talks about the protocol to be followed to read Mathematics. Also he talks about reading protocol in general.
So there is no one way to read every subject. If someone comes up with one mostly likely it will be a man-with-a-hammer.
I am a very slow reader. For a very long time I wanted to improve my reading speed and I tried many techniques but failed eventually. But in the process I realized that it’s ok to read slowly and its not a race that I want to win. Read this excellent article which talks about it.