Credit: Travel + Leisure After visiting more than 70 countries and learning to live out of a carry-on for weeks at a time, I’ve made every packing mistake in the book—literally. From cramming too many “just in case” outfits to forgetting something as simple as a charger adapter, I’ve found myself spending way over budget just to account for all the things I’ve forgotten. Over the years (and countless gate checks later), I’ve learned that the right gear makes all the difference. Whether you’re a minimalist traveler or a chronic overpacker, here are the most common mistakes I’ve made—and the products that actually solve them—so you can become a carry-on-only traveler.…