Hold the elevator
Yes, it’s simple—but holding the elevator or door for someone goes beyond chivalry (women: hold the door for men, too!). In a perfect, kind world, holding the door for someone would not even require a second thought, but, alas, it seems to be a habit of the past. You never know—that person rushing to the elevator could be late for a career-changing meeting—and your act of kindness could buy them a few minutes of time.