Be Practical.
Traveling is not cheap and traveling by car is not exclusion. Plan what your goal is and what you would like to achieve in your trip. The world is very big, select a specific itinerary that will take you to places that really interesting or/and important to you.
Define the Rout.
You should draw up an itinerary dependent on the country's roads and highways. Keep in mind that roads in developing countries and even outlying regions of developed countries might be very poorly maintained. Also take the seasons into account since roads are weather-dependent. You will not be able to drive on the iced, washed out or flooded roads.
Have First Aid Training.
There are different situations might be on the road. The death rate on the roads especially in developing countries is too high. If you are involved in an accident, a little First Aid training might save life for you or your passengers, or others involved.
Have good knowledge of traffic rules.
As many countries in the world as many different traffic rules. Every country has its own traffic laws. Moreover, in some countries its regions can have their specific variations. Learn the traffic rules of the countries that you are going to visit before you leave your home country.
Obtain an international drivers license.
Study the requirements to drive legally in the country you want to drive. Some countries might not recognize your domestic driving permit. In this case, you need to get an international drivers license that is an international translation of your national driver licence.
Get all documents necessary for travel.
Before you leave your county, get all documents needed for travel: passport, visa, car registration, insurance, etc. Don't forget about vaccinations. Remember that some countries have
Make decision what car to use.
Think careful what car to use for traveling. Your own car might not be permitted to cross borders. And, it might be easier to find/change rental cars at borders. You should think over and consider different critical situations.
Check where cars can go.
There are some places in the world where cars are restricted. You need to take into consideration places such as the heritage areas, sand dunes, etc. Don't forget about "resident-only cars" areas. Take also the traffic tolls into account to avoid during peak hour traffic, vacation seasons, festivals or religious events, etc.
Plan your stay.
Remember, everywhere you go, your accommodations will need to be able to cope with housing your car. In built-up areas or areas of high auto theft, this might be problematic. Ask what parking deals are offered. Always park your car in well-lit areas, don't leave valuables in the car or hide them out of sight, lock your car. It is always better to park in pay parks that are undercover.
About Unofficial International Drivers License - International Translation of the Original Driving Permit