As a final point, I will return to how you leave the interview.
It’s often said that you only have one chance to make a first impression: it’s also true that you only have one chance to make a final impression.
If you have put your bag on the floor alongside your chair, pick it up before you stand. Put your notepad in it. This shows confidence and organisation and an ability to plan and execute a strategy. It sends a subliminal message.
Stand, facing the panel and straighten your clothes. If they stand and offer to shake hands, do it, with each in turn. Shake the hand of the one who is in charge last. To each, say Thank You and nothing else. If they do not offer to shake hands, do not offer.
Stand straight, chin level, and turn. Do not struggle to put your bag on your shoulder. Carry it. Do not lean forward as you walk. It makes your bum stick out. Shoulders back, chest out, buttocks taught. Keep your feet pointing forward, not turned out.
Remember the basic rules taught to all catwalk models: teeth, tits and toes.
If you tip forward, lift your chin, stick your bum out and walk with your feet pointing out, from the back you will look like a duck and that is the only thing the panel will remember from the whole interview.