Chapter One - Mishna 15 (3)
And greet everyone with a cheerful face
He ends: "Welcome every person with a cheerful face." Show everyone you meet that you are happy to see them. Speak to them in a nice and friendly way. The Torah considers this the best gift you can give another person. Everyone knows how scary it is to be a new person in a school. Think of how good you would feel if someone smiled t you and said "hello", when you were uncomfortable. Even when someone is not new, but feels a little sad, greet him in a cheerful way. It may chase away the sadness.