No matter what you do, try to do it as well as it can be done.

Have nothing to do with the inferior.

Do your best in everything; deal with the best; choose the best; live up to your best.
Everywhere we see mediocre or second-class men--perpetual clerks who will never get away from the yardstick; mechanics who will never be anything but bunglers, all sorts of people who will never rise above mediocrity, who will always fill very ordinary positions because they do not take pains, do not put conscience into their work, do not try to be first-class.
Aside from the lack of desire or effort to be first-class, there are other things that help to make second-class men.

Dissipation, bad habits, neglect of health, failure to get an education, all make second-class men.

A man weakened by dissipation, whose understanding has been dulled, whose growth has been stunted by self-indulgences, is a second-class man, if, indeed, he is not third-class.