This is a great tip:

"Step One.

The first thing I do when I pick up a book is read the preface, the table of contents, and the inside jacket. Often, I’ll glance over the index too.

This doesn’t take long and often saves me time, as a lot of books do not make it past this filter. Maybe it doesn’t contain the information I’m trying to gain. If it seems crappy, I’ll flip to a few random pages to verify.

This filter is a form of systematic skimming. This isn’t my term, Mortimer Adler, a guy who literally wrote the the book on reading, came up with it.

Adler says there are four levels of reading. I tend to blend inspectional reading and analytical reading together for most books.

When I start reading the book, I have an idea about what it’s about, the main argument, and some of the terminology involved. I know where the author is going to take me and the broad strokes of how they will bring me along.

So then I finally start reading. While reading I take notes. I circle words I need to look up. I star important points that I think are critical to the argument. I underline anything that strikes me as interesting. I comment like a mad man in the margins. I try to tease out assumptions. etc.

Essentially, I’m trying to engage in a conversation with the author."

Essentially, use the book's periphery to decide if the book is worth your time.