You will to have a valid passport. Check to see if a visa will also be required for where you are going. Read the Consular information sheets for the areas you are traveling to prior to leaving. This will provide you with up to date information of anything taking place in that region that you should be aware of. If you do find yourself in any type of legal trouble, immediately contact the US Embassy for assistance.
Rules, regulations, and laws are different in Asia than in the United States. It is wise to familiarize yourself with the policies and procedures of that area. You don't want to find yourself in legal trouble out of the country because you weren't aware of how things are done there. Follow there rules set by all airports of not leaving your bags unattended or attending any type of package from someone you don't know for any reason.
Basic rules that apply anywhere including wearing expensive jewelry and clothing and showing large amounts of cash. These are indicators that you have items of value. It can lead you to being the victim of a robbery or worse crime. To avoid being the victim of a scam don't exchange currency with anyone except an authorized agent. Fully investigate prior to making purchases such as jewelry, art, and antiques.
Traveling to Asia can be a great experience. If you take the time to follow these basic tips, you will be more likely to enjoy your trip as well as return safely. By being prepared, you will be able to avoid surprises that will ruin your trip. By registering with the US Embassy, you will have an ally in the case something does take place. Having all these things in place will help you be able to focus on the beauty of Asia.