If you go the docker-machine route, you can do the following.

    brew install docker-machine
    docker-machine create --name myserver ...digital-ocean-options
    eval $(docker-machine env myserver)
    docker ps

that is:

* install docker-machine

* provision a droplet with docker on it (you can also use test.docker.com to use an RC instead of the latest release)

* set your local shell env to point docker to said machine

* use the docker client to interact with said machine

I also use docker-for-mac and a similar process to spin up swarm-mode clusters. You can also ssh into the machine if you need to by `docker-machine ssh myserver`

[0]: https://docs.docker.com/machine/drivers/digital-ocean/