tmux uses Ctrl-b as the default command prefix, that's ok on Windows but less than desirable on a MacBook Pro. Turns out that it's super easy to remap to something easier to type, but it's a two-step process.
First, let's get some usage out of the vestigial 'caps lock' key. Go to 'System Preferences' -> 'Keyboard' -> 'Modifier Keys' and then change caps lock to do something (marginally more) useful, the Control key.
Now that that's out of the way, remap the prefix in tmux by editing (or creating) your ~/.tmux.conf file. We only need one line in there to remap the prefix to Ctrl-a (which are handily right next to each other):
set -g prefix C-a
Two things to note: first, changing the caps lock key to be control affects ALL applications on your Mac, if you're like me and never use caps lock, that's probably ok - just something to remember. Secondly, sometimes you might want to be able to send Ctrl-a to an application that you're using inside tmux. If you think you will, just add another line to your ~/.tmux.conf file:
bind C-a send-prefix
This will allow you to send Ctrl-a to the application running inside tmux by pressing it TWICE.
