Bonus: Just one thing can solve 3 problems at once.
Your outfit should have many layers. First, it could be pretty cold on the plane during the flight. Second, in case there is smoke on the plane, you will have something to cover your face with. And finally, if your baggage is lost, you won’t have to wear just a T-shirt in a cold foreign country. A universal solution is a big scarf. But there is a trick: you need to wear it correctly. Don’t tie it around or wrap your neck with it. In case of evacuation, there’s a risk of getting a serious injury.