For me...
- Desktop has to be clear,
- If I'm not using an app, I have to quit it,
- Web browser has to be top hand left of screen aligned with the edge of the top menu bar,
- Web browser about 3/4 of the screen across, then in that space Mac:Messenger goes there and any chat windows in remaining top space,
- Don't like anything in the trash,
- All fider windows have to be the same size.