Smile (a lot). No one wants to choose a grouchy beauty queen or one who seems inaccessible, arrogant, or who lacks confidence. Smile! It will immediately give people a good impression of you.
Have excellent posture to walk like a queen. Beauty queens have great posture. This is absolutely crucial. You need to walk regally, with your shoulders back and head straight (never looking down). Show confidence at all times. You can walk with confidence, too. Don't crunch your back. Stand up straight! Not only will you feel more confident and beautiful, standing up straight helps improve your mood, memory, and boosts creative thinking.