These books are great for learning Nepali. To use them, start by reading through the chapters systematically. Take notes and practice the language concepts presented. When you're done reading, keep them on a flat surface to avoid further bowing. To clean the covers gently, use a soft, dry cloth. Don't expose the books to excessive moisture or direct sunlight as it can damage the pages and covers. If you're not using the dust jackets, store them flat to prevent creasing.