Ditto to the readme on GH. The key (ahem) bits:

1. Create ~/.karabiner.d/configuration/karabiner.json 2. Put some stuff in it (my simple example below) 3. Install the app from the GH page.

Key definitions are in the source code, but if you check the Issues discussion on the Elements project, you'll probably find good examples to send you on your way.

Sample karabiner.json: { "profiles": [ { "name": "Default profile", "selected": true, "simple_modifications": { "right_option": "delete_forward" } } ] }