The best way to set static IP is to use the router’s DHCP reservation (or called IP reservation) feature, which binds a specific IP to the MAC address. This way, if OpenGarage reboots, or router reboots, the IP assigned to it will remain the same.
while that may be the ‘best’ way it is not an option in my router. I am assuming from your answer that the opengarage device does not have the ability to set a static IP in the web interface? Isn’t it based off the same hardware and software as the opensprinkler (which I also have)?