That is a very good question @chino-aztv, that was one of the very first questions I had when I started researching Flat Earth.
When it comes to navigating everything is oriented from North. A compass points towards north. If you are traveling due east north will always be on your left if you're traveling Due West North will always be on your right. This works the same whether you're navigating on a flat disc or on a ball. On a ball North is at the top were as on the flat disc it would be at the center. So if North is the center of the disc than the extreme South would be the edges. What is at the extreme South of the Earth?
Now what about other planets ? Are they flat as well ?
That is another great question. If you are a person of faith and believe the Bible to be true let me ask you does God ever mention other planets anywhere in his account of creation?