Start slowly, keep the wrist FREE!

This piece is good practice, because you'll have only one finger acting - at the same time - on in the left hand. This will enable you to concentrate on your right hand: Play with your wrists free and loose! Start slowly; practice this piece every day for few months! (Up to 15 minutes a day).
Later, try few right hand fingering combinations such as: p - i a m and p - m i a.