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Whenever I ask someone how I can improve my writing overall, they almost always suggest reading more.

However, I was wondering what sorts of books/other things should I read in order to improve my writing?

From your personal experience, what types of books have made you a better writer and thinker?

You can read some classical books

Stephen King's nonfiction: On Writing. Very helpful tips!

One good way to put the advice into practice is to choose a book you have read, but which you thought wasn't that brilliant (don't try this with a book you really, really love, because you'll never be able to look at it the same way again!). What book it is, doesn't matter - just something you've read, and at the end of it you thought "Well, that was average."
Read through it again, and this time, pick it apart. You didn't like a certain scene? What exactly didn't you like about it? How would you have written it better?
Does a certain character do something you think doesn't make sense? Why did they do that? What would you have written instead?
What about descriptions? Can you see the scene in front of the hero? If not, what's wrong with the description? How would you improve it?
That's a good way to improve your own writing.