First and foremost, be faithful to your superiors, keep all promises, refuse the friendship of all who are not like you; and if you have made a mistake, do not be afraid of admitting the fact and amending your ways.
He who learns but does not think, is lost! He who thinks but does not learn is in great danger... Men of superior mind busy themselves first getting at the root of things; when they succeed, the right course is open to them.
Old age, believe me, is a good and pleasant thing. It is true you are gently shouldered off the stage, but then you are given such a comfortable front stall as spectator.
Please stop waiting for a better and more appropriate time to become happy and focus on the moment you live in. Happiness is not an arrival, it is the journey itself. Many people seek for happiness above the height of human beings, some below. Yet, happiness is exactly at the exact height of human beings.