From John Gimlette, travel writer
Carry pictures of your family. They are a great way of communicating your harmlessness, especially where language is an issue. If you don’t have family, take pictures of the Royal family. They are often a source of interest.
Pack a tin of sardines in countries where foodmight become tricky. They are good for emergencies but just sufficiently unappetising that you won’t be tempted to eat them prematurely.
Take your old work shirts (those with frayed collars etc). Cotton is great in all climates, and you can give them awayas you go. I often come back with an empty suitcase!
If you think you’re in an unsafepart of town, avoid eye-contact, look as if you know where you’re going and do not display a guide book.
Try and avoid Western-style food in countries that have their own distinct cuisine. It may not have been cooked properly, and may have been sitting around for ages. Even in big hotels, the Indian variant of the full English Breakfast can be lethal.