How do I add a book to my own bookshelf?

From the book info page, select "Add to bookshelf". Then select the bookshelf you want to add the book to and select "Save". Alternatively, select "Select books" on the home page ("Bookshelves") or from e.g. a search or a themed bookshelf. Select the book or books you want to put on a bookshelf. Select "Add to bookshelf". Then select the bookshelf you want to put the book in and select "Save".