The most important part is watching them so closely its not possible for them to potty somewhere.
Thats atleast what made it click with Joel, I didn't LET him have an accident and he forgot how to "go" in the house lol.
But when he kept having accidents I was getting frustrated and wondering what I was doing wrong, so I would set alarms and leash him to me, or whatever I had to do for him not to go potty in the house, and after a few days of no accidents is when I saw him figuring it out, and then he would just start telling me.
Now he's 8months and I dont remember the last time he had an accident and I no longer even remind him to go out, only when he first comes out from the crate, all he knows is to go to the door and whine or bark.