When you play, never mind who listens to you.
Play always as if in the presence of a master.
If any one should place before you a composition to play at sight, read it over before you play it.
When you have done your musical day's work and feel tired, do not exert yourself further. It is better to rest than to work without pleasure and vigour.
In maturer years play no fashionable trifles. Time is precious. We should need to live a hundred lives, only to become acquainted with all the good works that exist.