This repository contains a makefile that will generate Xmodmap mappings from your current (QWERTY, maybe localized) keyboard layout to the Tarmak 1-4 layouts.
Tarmak is a set of keyboard layouts that will help you transition from QWERTY to the Colemak keyboard layout. Tarmak consists of 4 different layouts, each changing 4-5 keys from the previous layout.
Normally, you'd transition from:
QWERTY --> Tarmak 1 --> Tarmak 2 --> Tarmak 3 --> Tarmak 4 --> Colemak
For some people, this will be easier than switching to Colemak cold turkey - and you can still be somewhat productive throughout.
DreymaR, the author of Tarmak, has a big bag of tricks that contains XKB layout files for Tarmak 1-4. Tarmak is supposed to be a temporary layout, and i think that bag of his is way too big - I'd rather not rewrite most of my XKB layouts for something i will hopefully just need for a few weeks.
Although deprecated, Xmodmap is perfect for this task. XKB still has a compatibility layer for Xmodmap - and Xmodmap makes it very easy to create and use transitional keyboard layouts like Tarmak. It will also work per-user, as xmodmap won't touch the system-wide XKB layout files.
First of all, check out this repository (git clone https://github.com/olemartinorg/tarmak-xmodmap) or download the Makefile to your local machine. Run make inside the directory containing the Makefile. Now you can start using the Tarmak 1 by calling:
xmodmap tarmak1.xmodmap
Good luck!