Having books is an objectively good thing. They teach you things, they help you relax, and, frankly, they let you look a little smarter in front of guests. But if they're messy, that last one falls apart. Your books should be well-organized, not only because you want to flex when company comes over, but because you should keep the things that allow you to learn and relax accessible to you.
First, let's talk about what to do if you already have a bookshelf but it's looking a little jumbled. The first thing you should do is take all the books off and sort through them using a decluttering method of your choice, getting rid of anything you don't need by donating it to a local shop or library. The problem with books is that they're among the easiest kinds of items to generate excuses about when you start weeding through them. Don't allow yourself to say, "But what if I need to reference this chapter about the Russian revolution of 1905 one day?" Unless you're a Russian history scholar, you probably won't. Be serious. You likely won't crack this book ever again and if you do need a little info, it's available online. Having too many books you'll never read again isn't a badge of honor; it's a cluttered mess that makes the books you do want to read harder to access.
Once you've pared down your collection, it's time to put the tomes back on the shelf. Categorize all the books you took off however you want. You can make piles based on size, color, or genre, but you should keep all of them together once you put them back in their place. Use the Organizational Triangle system of thinking for this: Every item must have a place and be stored with similar items. For what it's worth, my books are organized by subject, then alphabetically by the author's last name within those chunks, but I'm a former Barnes and Noble employee, so those habits die hard.
Another thing B&N taught me about sticking books on shelves is that they have to look nice, so consider separating your sections with something, whether it's a picture frame or a decorative storage box. If you have space, you should pull your favorite books out and turn them to be front-facing. This breaks up the monotony on the shelf and makes the whole display more visually appealing.
I'm lucky that my apartment has a built-in book shelf above a window and I have a smaller shelf on hand to store the books I regularly read and want access to, but there are a lot of really cool shelving options out there if you need a place to start.
First, I've seen some cool hacks online suggesting you should use straps to hold your books individually on the wall, creating a kind of gallery wall of them. That's a little too labor-intensive for me, but this shelf with straps built in is not. You secure your books into the straps on the underside of the floating shelf, then place whatever else you want on top, making it an ideal storage tool.
If you don't have wall space, I like this tree-shaped shelf. Its footprint is so much smaller than a standard bookshelf, making it easy to fit into smaller spaces, but it also creates an eye-catching look. There are separate sections within it, so you can organize your books by category.
A front-facing bookshelf is good for anything with an interesting cover or unusual size that might disrupt the flow of a more traditional row of books. This shelf has both standard and front-facing shelving, to make sure everything you have fits somewhere.
Finally, for true accessibility, why not consider a rotating bookcase? This is pretty enough to act as a decoration all its own, plus it allows you to access any book quickly just by spinning it around, so you don't have to think too hard about putting the books you use most in a shelving spot that's easier to get to; they're all easy to get to.
