Use Homebrew; it's simpler than ports.
CMD+` switches between apps in a slightly more sane way than CMD+TAB.
Don't unplug monitors or let the machine go to sleep with an ethernet dongle in it unless you like pain.
Make the dock auto-hide and use as small an icon size as possible and sit on the farthest-right monitor (i.e. where you're least likely to open it)
Use spectacle so you can maximise windows and so forth with the keyboard like you can in decent window managers.
Treat everything as case-sensitive even when it isn't.
Install a better terminal than the shonky one that ships with the OS.
You can drag some of the random notifications off screen to get rid of them (not all).
Use the keyboard shortcuts to disable CMD-Q by mapping it to something obvious but safe like "invert colours".
Basically, if you're anything like me, you're going to have a bad time and you should practice damage control.
Yeah, I'm a big fan of Homebrew and spectacle. I mention them in my Mac setup in this post. I started scripting my setup. Not complete, but does the job for now.
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