1. The base layer
Start with a breathable top and bottoms that allow you to sit, walk, and lift a bag comfortably. Keep metal, complicated fasteners, and accessories to a minimum if you want a simpler security routine. The best base layer is one you have already worn for a full day.
2. The useful layer
A cardigan, overshirt, or light fleece can serve as warmth, a pillow substitute, or a modesty layer. It should be easy to remove and easy to stuff into the personal item. Choose a neutral layer that works with the rest of your trip wardrobe.
3. The footwear decision
Wear the pair that can handle the longest walking day, not merely the shortest security line. If you bring a second pair, keep it light and purposeful. Airport comfort is cumulative: fit, temperature, luggage weight, and access matter more than one clever garment.
The short version
Choose for your real route, test the decision before departure, and verify changing airline or product details from authoritative current sources.