For those of you who use JOSM, I’ve published a diary of tips and tricks on how to create buildings (and shapes in general!) of varying complexity, perfectly.
I’m sharing it here because I think it might be useful to a wide audience of JOSM users! It was featured in WeeklyOSM 737, but well, maybe some people didn’t see it.
Enjoy 
Koreller's Diary | Building drawing tips, a perfect guide | OpenStreetMap !