For the country you are on, you have to answer with an unanswered bordering country. You eliminate all countries that don’t fit Rule No. 1. then the 2, etc. until there’s one country left. If after a rule no countries fit, you ignore it. The country you answer with is the next in chain and you continue the same way from there.
If the country you are on has no unanswered bordering countries left, then move back in the chain till you hit a country with unanswered bordering countries and continue from there.