$ git clone git@github.com:docker_user/docker_practice.git
$ cd docker_practice
# Update the content
$ git commit -a -s
# In commit msg dialog, add content like "Fix issue #235: describe ur change"
$ git push
$ git remote add upstream https://github.com/yeasy/docker_practice
$ git fetch upstream
$ git rebase upstream/master
$ git push -f origin master