sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D
curl -sSL https://get.docker.com/ | sh
Log into Ubuntu as a user with sudo privileges. This procedure assumes you log in as the ubuntu user.
Log out and log back in. This ensures your user is running with the correct permissions.