Ask HN: How do I clear my mind and regain focus?

Over the last couple of years my mind has become like a dull pencil and this only seems to accelerate as time goes by. I think the core of the problem is some kind of information overload. I have a list with over ten thousand bookmarks and everyday I add a larger number than I process. I also have a list with a few hundred books that I want to read. Beside that I have dozens of half-finished projects and many more unstarted.

If I try to read a book, process a bookmark from the list or work on a project, I am unable to focus on the task even though I find it very interesting, it is like my subconscious mind is focusing on all the other things I need to do. Tragically, the only area where my mind is not impaired is when it comes to accumulating even more bookmarks, I'm able to do this for hours with great focus.

I do not drink or smoke and I exercise regulary.

I know that meditation can be used to clear the mind, but after some research I learned the field is incredible broad and often goes much deeper that just clearing the mind. This also means that I am able to add hundreds more books and bookmarks to my lists which I really do not need.

Can you recommend me a single resource that explains the steps to clear my mind and regain focus?