Sorry, crooked isn't the best word, but I can't think of a better one.

I'm still quite new to OSM, and I want to start adding the buildings in my town. When I open the edit option though, the map overlay is at an angle. It's not a massive amount, but it's enough that you can see one sometimes two sides of most buildings, so the roof isn't aligned straight down, if that makes sense?

I live near Aberdare in South Wales, and you can see that where someone has added some buildings in the town centre at some point, they're now not aligned with the map overlay:

https://www.openstreetmap.org/edit#map=20/51.71312/-3.44499

Do I draw around the roof that I can see on the map? Do I edit the existing buildings so that they line up with the overlay? I'm not sure what the best course of action is for something like this.

Thanks in advance :)