Stay regional
Start with one continent. A smaller answer set helps you form useful groups and contrasts.
Choose a region and train country–capital pairs in a focused ten-question round. Missed answers become your review list; nothing you type is uploaded.
Use this trainer to learn the names. Then use Earthgame to attach those names to real positions on the globe.
Trying to produce an answer strengthens memory more than repeatedly reading the same list. A short round also makes it obvious which pairs need attention.
Start with one continent. A smaller answer set helps you form useful groups and contrasts.
After every answer, say both the country and capital—even when you were correct.
Finish by locating missed countries in Earthgame so the name gets a geographic address.