Avoid non-tourist areas and If you do feel uncomfortable, switch train cars or walk into very busy areas such as a restaurant.
Don't leave your drink unattended anywhere at all.
The best and fastest way of researching is to search on the Internet for legal information and things you should know well in advance of traveling to that country.
Leave important documents and your Passport in your hotel room, then if you somehow get robbed you still have them things that you really need.
If it is a certified taxi driver, then make sure by asking for identification. If you find out too late that you are in an illegal taxi driver's car, break away through windows or the door.
Make sure the doors open from the inside. When you arrive at your destination, have the money ready immediately and do not linger in the car.
Remember that the tap water may be treated with different chemicals from those in your home country and could make you ill if you drink it, especially for children and the elderly.
Always check that the car and driver that you're going to use is fully licensed with the local authorities.