How to update RaspBee II on my Rpi?

Cant figure this out despite reading alot of thrads all over the web for the last few days. Followed the instructions on Raspberry Pi - Home Assistant when I installed my HA. Have also installed Terminal and SSH on it. I have suceeded to download the firmware inside of Terminal, but I can not figure out how to flash it. Anyone with some suggestions?

Br
Freddy