First thing was to make my home Raspberry Pi running Hass.io available from internet. Obvious idea was to go through some VPN etc.. But then I stumbled upon service called Ngrok and eventually to Serveo.net that is amaizingly easy to set up and there is Hass.io add-on. But even simple:
ssh -R myalias:80:localhost:8123 serveo.net
did the trick to expose my Hass to internet.
Then I turned to the tutorial mentioned above and done .. easier than expected.
Now it's just "Hey Google .. Activate Standing" :-)