Avoid: Uncomfortable shoes *cough* high heels *cough*, jumpsuits that make for frustrating bathroom trips, fabrics that wrinkle or are restricting to sit down in, jewellery you'll have to take off at security, and tightfitting pants you'll be dying to unbutton (unless, of course, we're talking leggings).
Instead try: Breathable fabrics with comfortable details like elastic, and layers, so it's easy to adjust your wardrobe based on the ever-changing temperature as you navigate your way to your destination. Shop for thick compression socks, baseball caps or beanies, scarves, and all season jackets that will provide extra comfort, but can also be worn again later throughout your trip.