Essentials: Some elastic, a board, brackets and a stapler In short: this is made of stuff that many of us already have on hand or can purchase inexpensively at any hardware store.
The result: a book shelf that holds as few or as many books as you want , appears to ‘hang’ them impossibly above and does no damage to your favorite volumes. Books can then be easily added to and removed from the finished wood shelf.
Ta-Da.