I recently read a Reddit post where the author was asking for advice on reading more critically and in-depth, looking for deeper meaning than simply consuming words.
https://www.reddit.com/r/books/comments/2r45mw/how_to_read_critically/
I'd just continue reading what you enjoy, taking your time more than rushing through to move on to new books. Re-read pages and sections if necessary to really get your head around concepts. I re-read almost an entire chapter of Heinlein's Moon is a Harsh Mistress just to get a better idea of what he was trying to convey, and my perspective on his ideas.
Read reviews and analysis from other authors and critics, but take the opinions of others with a grain of salt.
Read the classics. Put together a list, or steal someone else's top 50 and work your way through them. You're also more likely to find criticism and reviews of popular works than obscure ones.
For non-fiction, step outside your comfort zone, read work from political philosophers, sociologists, and others that runs contrary to the views you hold. If you're a hard-core anarcho-capitalist, throw in some Marx to either sway you or ground you further in your beliefs. The worst thing a person can do is only read works that support an initial perspective or ideology.
Have fun, above all, for when literature becomes a chore, you'll find yourself in front of the idiot box too often when a good book is what you're craving.
