System: Debian/Ubuntu/Fedora. Might work for others as well.
1. Uninstall the existing version
As mentioned here, to update a Go version you will first need to uninstall the original version.
To uninstall the existing Go version, delete the /usr/local/go directory by:
$ sudo rm -rf /usr/local/go
2. Install the new version
Go to the downloads page and download the binary release suitable for your system.
3. Extract the archive file
To extract the archive file, run:
$ sudo tar -C /usr/local -xzf /home/<your-user-on-Ubuntu>/Downloads/go1.18.2.linux-amd64.tar.gz
4. Make sure that your PATH contains /usr/local/go/bin
$ echo $PATH | grep "/usr/local/go/bin"