$ sudo groupadd docker
Add your user to the
$ sudo usermod -aG docker $USER
Log out and log back in so that your group membership is re-evaluated.
If testing on a virtual machine, it may be necessary to restart the virtual machine for changes to take effect.
On a desktop Linux environment such as X Windows, log out of your session completely and then log back in.
On Linux, you can also run the following command to activate the changes to groups:
$ newgrp docker
Verify that you can run
$ docker run hello-world