1. Use a mild dish soap and water. Mix a small amount of dish soap with water to create a soapy solution. Dampen a soft cloth with the soapy solution and gently wipe the sticky keys. Be careful not to use too much water, as this could damage the piano.
2. Use a cotton swab with rubbing alcohol. Dip a cotton swab in rubbing alcohol and gently rub it over the sticky keys. Be careful not to use too much rubbing alcohol, as this could damage the piano.
3. Use a pencil eraser. Gently rub the sticky keys with a pencil eraser. Be careful not to use too much force, as this could damage the keys.
4. If the keys are still sticky, you may need to have the piano professionally cleaned. A professional piano technician will be able to safely and effectively clean the keys and restore them to their original condition.