On the Automation homepage you will see a listing of all the automations that you have created. On each row of the display is an actions cog that allows you to:
Taking View/Edit will allow you to see the number of contacts who have started the automation and the number of have completed all steps.
You will also see a listing of all the existing steps. For each step you have an Actions Cog. The options on the Action Cog depend on the type of step.
The available actions are: