The board came with ToradexEasyInstaller and I was able to install the image (Colibri-iMX6_LXDE-Image_2.8b6.184-20190401.tar.bz2).
Now for the next step I want to install my own image (build with oe-core as explained in the knowledge-base).
I was following
https://developer.toradex.com/knowledge-base/flashing-embedded-linux-to-imx7-modules#Preparation
but there is no update.sh script provided with the image nor the prebuild Linux LXDE Image provided on the same page.
I am also not sure if I have even chosen the right (or best) approach to deploy a new Image.