MacBook Air and an external monitor: a window layout that works

Put the work you look at most on the monitor, and things you glance at, like chat, mail and music, on the laptop's screen. Then make the arrangement in System Settings, Displays match where the screens really sit.

Setup steps

1. In Displays, drag the screens so they match your desk, and choose the main display (the one with the menu bar).
2. Pick a scaling on the monitor that fits three windows across.
3. Decide on Displays have separate Spaces in Desktop & Dock: on gives each screen its own desktops.
4. Check Apple's tech specifications for how many external displays your model supports.

When you unplug

Every window on the monitor moves onto the laptop screen, usually stacked on top of each other. See windows moving after unplugging and, if you close the lid, clamshell mode.

A strip on each screen

ClutterFreeMac keeps a strip of windows on each display. ⌃ ⌥ N sends a window to the next display, and when a display comes or goes the strips are checked against what is open, so nothing is left parked off screen.