Avoid round trips, zigzags and limit the number of flights.
Once we have our country base, we must succeed in linking them. It is then a real work that begins! Flights should be studied when they are unavoidable (where to go from and where to arrive) and the land borders between each country. To do this, the Internet is your best friend.
The best is the opinions of travellers who have already done part of your journey. Following this step, we added Malaysia (arrival by plane from Sri Lanka and crossing the land border with Thailand), Chile (the only entry point into South America from New Zealand) and Paraguay (transition from Puerto Iguazu in Argentina to entry into Bolivia).