Rules from making friends. As a proverb goes, we can judge a man by the company he keeps.
So it is very important to keep a good company. A good friend is someone who can be with you whenever you need him.
There there when thing is good and also there when the thing is bad. To choose a friend, you have to choose someone who has the same interest as you have.
As a friend helps you in your time of difficulty. You must also help him in his hour of need.
As the saying goes, a friend in need is a friend indeed.