The image can be found on Docker Hub.
It is necessary to have Docker installed to be able to use one of the following commands to start a container. This will start a new container and mounts your current directory in the container to be used with Theia. Theia can be accessed via localhost:3000.
Linux:
docker run --init --rm -it -v $("pwd"):/home/node/project -p 3000:3000 philipdeussen/theia-wf-test
Windows (cmd):
docker run --init --rm -it -v %cd%:/home/node/project -p 3000:3000 philipdeussen/theia-wf-test