First, you need to have these principles ready. Don't do anything without them. Keep your mind focused on this goal: don't chase external things or things that belong to others. Instead, do what the one in charge has assigned you to do. Go after the things that are within your control. Accept everything else as it's given to you.
Next, remember who you are and what your role is. Try to match your actions to your different relationships in life. Know when it's time to sing and when it's time to play. Know who you're with. Think about what will happen. Will your friends look down on you? Will you look down on them? Know when to joke and who to make fun of. Know when to go along with others and with whom. And when you do go along, keep your character intact.
Whenever you break any of these rules, you damage yourself immediately. Not from anything outside you, but from the action itself.
First then we ought to have these (rules) in readiness, and to do nothing without them, and we ought to keep the soul directed to this mark, to pursue nothing external, and nothing which belongs to others (or is in the power of others), but to do as he has appointed who has the power; we ought to pursue altogether the things which are in the power of the will, and all other things as it is permitted. Next to this we ought to remember who we are, and what is our name, and to endeavor to direct our duties towards the character (nature) of our several relations (in life) in this manner: what is the season for singing, what is the season for play, and in whose presence; what will be the consequence of the act; whether our associates will despise us, whether we shall despise them; when to jeer ([Greek: schopsai]), and whom to ridicule; and on what occasion to comply and with whom; and finally, in complying how to maintain our own character. But wherever you have deviated from any of these rules, there is damage immediately, not from anything external, but from the action itself.