How do I properly make a map ?

Most tutorials on YouTube are outdated or very misleading. Please help.

 

I have the same problem as you, I´ve searched everywhere to find a useful tutorial but all are indeed outdated. I´m still waiting for a more recent tutorial.
What I did to get a bit of a hang of the editor is just to start editing a bit of an existing map.
So just download a map or use a vanilla one, and get in the editor and start editing. It might be a good idea to back up the map if you start editing vanilla maps though.

 

This helped me.