Start from scratch

Take your time and empty the shelf including the shelf carpet. It’s so much easier to start at the beginning. Remove books that you no longer want

You could have friends that need them, or donate them to some other people instead of having them waste a lot of space and carry dust.  Decide how you want to categorise the books

Having books categorized makes it easy for you to access a book and at the same time, keep the shelf organised. Organise them by author, title, or subject. But if you want to organize them by height and colour that is also fine. Dust and clean the books

It’s quite useless to have a well organized shelf of dusty and dirty books. Before you put them back, take time and clean them properly. Organize the books aside

Spread out all the books on the floor and organise them in categories.Place binding side outwards

When placing the books on the shelf, make sure all of the book spines are facing you.