Know the local laws and social customs and abide by them.
Dress conservatively and try to blend in.
If you have not left your valuables at home, leave them in your hotel's safe.
Do not draw attention to yourself, avoid wearing flashy jewelry and do not 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.
Do not 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.
It is very important to enjoy yourself when on a trip, whether it be for business or pleasure and you must not be constantly thinking about what you should or should not be doing. Instead the tips below are meant purely as a guide, for you to take some points from and others to leave all together.
Try to look as if you know where you are going, this may not be so easy if after all it is the first ever time in that country, but even still look confident as IF you know.
Carrying maps around looking perplexed, and stopping to look at monuments or buildings, obviously shows that you are from out of town, and may attract the wrong type of attention.
Using travelers check, will always be helpful, as will using a credit card for any purchases made so that you can take advantage of the additional insurance offered.
Do not pull large amounts of cash out of your pocket. This will catch attention, no matter what country you are in.
Try to think about where you are going that day and carry sufficient cash for that and any unforeseen extras, plus a card. That should cover all you need and will limit any losses if anything did happen.
Do not accept drinks from anybody that you have just met, especially if in dubious surroundings or do not know, they could be laced with any type of concoction.
Try not to go on "wonderful trips" or to a "super shopping center" rides with people who approach you in the street. This could lead anywhere, and will probably cost you a lot more than by taking a normal taxi. Ask your concierge or read through this site.
Check on your first day whether you need to reconfirm your next flight, if so do it then. Some airlines do not require this anymore but it is still worthwhile calling them so that they at least have your contact details, in case the flight is delayed or whatever.
Do not carry your passport around; leave it in the safe in your hotel. A photocopy will suffice if local law states that you need to.