Know risks you face.

Do the research so you’ll know the particular risks you face. Know the local laws and abide by them.
Register your whereabouts with the U.S. Embassy if you are staying longer than two weeks or are in a particularly dangerous area.
Dress conservatively and try to blend in. If you are in an area with groups of people hostile to the United States, and there are many, avoid clothing or other items that openly label you as a U.S. citizen. Take care when choosing your hotel and transportation providers.
If you haven’t left your valuables at home, leave them in your hotel’s safe.
Don’t draw attention to yourself, avoid wearing flashy jewelry and don’t display large amounts of cash. Carry only enough cash to make it through the day and leave the rest in the hotel’s safe.
Avoid traveling alone.
Be careful about sharing your traveling plans with strangers.
Stick to the main roads and avoid taking shortcuts down narrow alleys and/or poorly lit streets.
Always be aware of what is going on around you.
Only use taxis, tours and other transportation services with official markings. Only select transportation from official pickup points at transportation hubs.
Be very careful if you are asked to sell or part with your personal items. Many countries have restrictions on items foreigners can sell or give away and you can get into serious trouble for violating those laws.
Never accept gifts or packages from unknown parties.
Don’t accept items from locals to carry out of the country and deliver or mail to someone they know.
Approach any "special deals" with caution, especially if you have to go off the beaten path to get them.
Know the laws about exchanging money. Only use official exchange facilities since this is another area that can get you into trouble fast.