Make sure you have Docker installed and follow the instructions for your operating system to have it running.
Then, chose the directory, where you want to have the dockerfile and run
$ git clone https://github.com/schruste/docker-ngsolve
$ cd docker-ngsolve
$ docker build -t ngsolve .
Don't forget the . at the end of the 3rd line!
Now, you need to start the container and both bind the correct ports of the container to the ports of the host and bind your directory with the code you are working on to a directory in the docker-container, i.e.
$ docker run --rm -t -p 8888:8888 -v /path/to/code:/home/jovyan/tmpdir --name ngsolve ngsolve
here you replace path/to/code with the actual file path to your code.
In the output, you will see something like this:
[C 15:41:40.343 NotebookApp]
To access the notebook, open this file in a browser:
file:///home/jovyan/.local/share/jupyter/runtime/nbserver-7-open.html
Or copy and paste one of these URLs:
http://(7e5ca25e26ff or 127.0.0.1):8888/?token=f476cc82d45039420f4778347f1387071d9083a022bb14ee
Now, just visit
http://127.0.0.1:8888/?token=$TOKEN
where token is everything to the right of the equal sign.
This should connect to the jupyter notebook server and show the content of the directory in /path/to/code.
You can close the server either with Ctrl-C in your terminal, or with $ docker stop ngsolve in another shell prompt.