These are the steps that you need to take to get Colemak keyboard layout fully working on your iMac or MacBook, including remapping Caps Lock to Backspace.
Installing the layout
Download Colemak.keylayout and Colemak-Mac-Icons.zip. Unzip and put them in your ~/Library/Keyboard Layouts
You will need to restart before they will be picked up by the system preferences.
Activating the layout
Having restarted, go to System Preferences -> Language & Text -> Input Sources and you should find Colemak as an available layout. You may want to tick “Show Input menu in menu bar” if you want an easy way to switch layouts. You can also play with the keyboard shortcuts for switching.
A tip for beginners: if you enable the “Keyboard & Character Viewer” at the top of the list then you can get a useful on-screen picture of the layout.
Mapping Caps Lock to Backspace
I found this is easily done with PCKeyboardHack. Download it, unzip it and install it. You will have to restart again, unfortunately. This is Serious Business we are doing here!
Having restarted, go to System Preferences -> PCKeyboardHack and tick the first option: Change Caps Lock to keycode 51 (Delete)
It feels slightly slow to respond and you can’t press and hold to delete many characters at once. I didn’t think i’d keep it, but just as i’ve been writing this blog post i’ve found i’ve got used to it extremely quickly (actually that says more about the number of errors i’m making at the moment!)
In any case my TypeMatrix has the backspace in the middle, which i think is an excellent place for it, and i don’t wish to annoy the people i pair with who like to have Caps Lock as an extra Ctrl key.
But there you go – that’s how you do it if you want to! :)
a little place of calm 
I was doing this for a while, but I’ve switched to using http://pqrs.org/macosx/keyremap4macbook/
It keeps the keyboard layout in more situations, such as admin password prompts and when using VMWare.
hey Xavier, do you use Colemak?
i don’t usually have any troubles with password prompts and virtual machines because i use a TypeMatrix which converts the keycodes at the hardware layer.
However, i shall try keyremap4macbook as well because i think it may enable some of the other functions of the TypeMatrix :)
Hi Aimee,
I’ve been using Colemak for a while now, and am very happy with it. It did take me longer than I expected to get the hang of it – my fingers simply refused to remap some letters to their new positions. The trickiest adjustments were typing ‘ls’ and ‘cd’ (!) and getting used to software that assumes a certain keyboard layout. e.g. games or vim. Remapping key settings can get a bit fiddly.
There is a Colemak .vimrc that would be good for vim newbies, but I just remapped j,h,k and l.
Actually, a tweet from Chris Parsons suggesting deleting and retyping every typo several times did help. Typing tutors were helpful in learning the layout (Ten Thumbs is a good one with Colemak support).
Hey Mark, great to hear from you. I agree, real words are much easier to type than acronyms. XKCD is a particularly hard one to type! ;)
I decided not to remap hjkl because then i would have to change other keys that are where they want to move to. How did you deal with that? It’s no big deal to me because i learnt vim with dvorak and the keys were never together for me in the first place. I just get used to the letters wherever they happen to be.
Thanks for the tip of Ten Thumbs.