Keep your hand and wrist relaxed. Keep your wrist straight not curved.
If a child is to low on the chair (check the elbows) put a pillow undernieth the child.
Hand Position
REMEMBER YOUR HANDS ARE OPPOSITE.
So are the left and right hand positions.
RIGHT HAND: your thumb is finger one. Finger One is on C (finger 2 is on D, 3 is on E, 4 is on F, 5 is on G)
your hand is on C position. If your finger one is on D you are in D position, finger one on E then E position and so on.
LEFT HAND: your pinky is finger 5. Finger 5 is on C (finger 4 is on D, 3 is on E, 2 is on F, 1 is on G)
your hand is on C position. If your finger 5 is on D you are in D position, Finger 5 is on E then E position, and so on.