What do you want to know @Casper181
Install Openhab on a NAS, install MQTT Broker on a NAS or Homey, Install the MQTT Client on Homey and install the MQTT Hub on Homey.
Setup all the applications. Push all the devices to OPenhab and start to install the widgets.
I have made several widgets. See https://github.com/marcelwolf/Openhab-widgets
Current dashboard
