The first priority in caring for your piano is to keep it in tune, which means A-440 or concert pitch. After your first year, pianos would be tuned at least twice a year; its a small investment to keeping your prized instrument working without needless expensive repairs, and producing delightful music as it was meant to when you first laid your eyes on it.
The next step is to keeping your piano clean. When not in use, always keep your keyboard covered with the piano key cloth cover that came along with your piano when you first purchased it; this prevents dust from accumulating (the exception here would be ivory keys, which need some exposure to light to prevent yellowing).
Make it a habit to clean the keys occasionally with a damp cloth and drying them immediately. Its important that you do not use chemicals or solvents to clean piano keys; if some dirt cannot be removed with a damp cloth, try wiping the cloth on a bar of mild soap or moisten with dishwashing liquid before wiping. Call a piano specialist to remove anything from the keys you cant wipe away.
The piano’s finish maybe maintained with a damp cloth to remove fingerprints; you may also use your manufacturer recommended emulsion-type, water based solution to polish the piano. Your piano specialist may suggest a suitable brand for this purpose. Avoid aerosol spray polishes that contain silicone.
The inner workings of your piano should be maintained by your piano specialist; resist any tendency to dust the inside of your piano, oil the moving parts, or use moth or insect repellants.
The location of your piano should be one where the temperature and humidity level is fairly consistent. Your piano should not be placed close to doors which open and close often, an air conditioning vent, or beside a window with direct sunlight streaming through.
Play your piano regularly. This will help any problems to be spotted sooner than later, as the longer it takes to discover the problem, the greater the damage that can result within. When a piano has not been tuned for sometime, a pitch raise maybe required. As your piano gets older, it may begin to develop more serious problems; consult your piano specialist to make an assessment before looking into rebuilding or reconditioning the piano.
Never leave your drinks or any standing liquid containers at the piano. Once the liquid spills inside, the damage is irreversible.
Do not perform repairs yourself. Though a problem may appear easy to solve, your piano specialist will have the proper tools and parts to make repairs quickly and correctly. It's important to remember that unsuccessful amateur repairs are usually much more expensive to fix than the initial problem, and may decrease the value of your instrument.
Use only a professional piano mover to move your piano. You will avoid injury to yourself, your instrument, and your home.