This gist will drive you through creating a Docker 1.12 Swarm cluster (with Swarm mode) on AWS infrastructure.
You need a few things already prepared in order to get started. You need at least Docker 1.12 set up. I was using the stable version of Docker for mac for preparing this guide.
$ docker --version Docker version 1.12.0, build 8eab29e
You also need Docker machine installed.