Docker Community edition for Mac comes with the following different components
Docker Engine
Docker CLI Client
Docker Compose
Docker Machine
Before upgrading checking the versions
$docker -v
Docker version 17.09.1-ce, build 19e2cf6
$docker-compose --version
docker-compose version 1.17.1, build 6d101fb
$docker-machine --version
docker-machine version 0.13.0, build 9ba6da9
If the Docker is running then from the top menu bar click on the Docker icon and navigate to
Check for upgrade