Some things are obvious: wear bland, low-key clothing, avoid expensive watches, and don't flaunt your gadgets. Others things, less so: if you have to load your fancy-looking luggage into the cargo hold—or, worse, throw it on top of the bus with the chickens—cover it with the same grain sacks/burlap bags the locals use. The trick is to mimic without mocking. Wearing a Yankees hat in Cuba (where they're everywhere) or an Adidas tracksuit in Venezuela (ditto)? Good move. Sashaying around Islamabad in a traditional shalwar kameez? Probably not. Just don't forget: manners always speak louder than garb.
"If you buy an Afghan scarf and act like an asshole," says Junger, "you're still an asshole."