Dress stylishly when abroad without packing your entire wardrobe.

Pick a compatible palette: neutrals or bright non-contrasting colors. I tend to pack earth tones and basic black. You can wear the colors more frequently without washing them (should you spill something on yourself it's less noticeable). Pack cotton knits, jersey, and other wrinkle resistant fabrics (who wants to look like rumpled bed linens?)

Limit yourself to 2 pairs of shoes (comfort and dress), one handbag, travel size toiletries (check latest FAA restrictions), minimal jewelry, and no need for pajamas. Use luggage with wheels that you can manage comfortably on your own if need be.

You won't stand out as an American tourist and when you look good, you feel good. Street vendors don't hassle you as much if you look like a local who's just going about their business.

I'm always flattered when I'm traveling abroad and another tourist ask me for directions because they think I'm a local. I love their surprised expression when I open my mouth and "American" comes out.