Learn driving and parking rules that are effective in the United States. You can get this information from the Department of Motor Vehicles in any city.
Get an international driver's license from your country of residence. Without this you are not allowed to drive or get insurance in a country you visit. Carry this license with you, as you will need to show it before you can get coverage.
Go online and look for insurance companies who specialize in providing insurance coverage to foreigners. Progressive, Allstate, Geico and AIG are some of the top companies in auto insurance.
Contact the insurance companies and collect information about the kind of coverage you want.
Ask the insurance company if you are eligible for a comprehensive policy that covers most of the risks of driving a car.
Ask the insurance agent if your name can be added to the policy of a relative or friend who resides in the United States. This can be an easier way to get insurance and may be cheaper too.
Get insurance from the car rental agency if you rent a car. This may be the easiest and the best option. However, do not forget to compare rental and insurance rates of different agencies.