Your conduct in public should be marked by quiet dignity. The keynote of good manners is unobtrusiveness.
When you are out in public, keep in mind three principles. The first is to treat everyone you meet with kindness. Your sensitivity toward those you meet may brighten their day.
The second is to take no one for granted. Be aware of the people around you and their rights to the public space you share. Don't simply ignore the waitress, the sales clerk, or the bus driver; be sincerely grateful for all services and thank those who provide them.
The third is to respect others. Be helpful to the elderly, the infirm, and the physically challenged.
— Mary Mercedes, A Book of Courtesy