How do I create multiple players when playing solo?

[schnel]

For the life of me, I can't figure out how to setup multiple players when playing alone. And I can't find a video that describes how to do it either. Can someone guide me or point me in the right direction? I think it involves changing my color to black, but I don't see how to "seat" additional players after that.

[Bone White]

Hotseat

However, hotseat has multiple issues. I play multi-seat in single player and just change seats when needed.

[schnel]

Got it. Actually, Hot Seat seemed to work okay. If I click Multi-Seat, it asks me to set up a server.