Avoid slouching over the piano, which can cause back injuries. Sit up straight with your head and shoulders upright, your rear end closer to the edge of the bench, your feet flat on the floor and your elbows slightly above the keyboard. Your hands should be curved and rounded over the keyboard. When you play, your wrists and knuckles should be at the same level and curved as your fingers are curved. Instead of lifting your wrist to reach a non-reachable note on the keyboard, move your elbow and shoulder forward in order to reach the key with your finger. Take breaks between your piano practice sessions and never play in pain.
Refrain from vocal straining. Use healthy vocal techniques that don't require vocal screaming or straining. If your throat hurts when you sing, stop singing. Never sing from your throat or lock your jaw when singing. Use your diaphragm to sing, and keep an open, relaxed jaw. Use the abdominal muscles and diaphragm and proper breathing to help you to execute your quality of sound. This allows you to control the amount of airflow and the longevity of a note, and to sing impossibly high notes without straining your voice. Take vocal breaks when singing to avoid vocal overuse and drink water before singing.
Avoid bad singing posture. Poor posture can pull down on the neck, shoulder and back muscles, which can cause injuries. When you sing, your chin should be parallel to the floor, and your shoulders pulled back and down. Hold your chest high, without growing tense. Keep your abdomen flat and firm, but held in an expandable position. Relax your hands. Also, stand with your knees relaxed and loose, not locked, and with your feet somewhat apart with one slightly in front of the other.
Make sure all instruments are working properly to avoid injury to students. Check your stringed instruments, such as guitars and violins, to make sure that the strings are secured. Make sure that the piano lid is secured so that it cannot fall down and cause injury to a student's fingers or other parts of the body. Never leave the instruments unattended during a classroom session. Place instruments that have cases back into their cases and secure the latch. Keep instruments away from heat and humidity, to avoid damage to the instruments. If you teach guitar lessons, make sure students wear finger protectors to avoid injury to the tips of their fingers.