In the Marketer account, click Templates > Create New Template. A pop-up will appear asking if you would like to use the Legacy Builder or Zephyr Builder.
Click Zephyr Builder to create a template in the new Zephyr Builder environment. You will be brought to the template creation page below:
In this pop up you will set a Template Title.
And choose a starter template to build from. Not sure? You can always choose 'blank' so you can start your masterpiece from scratch.
Click Save to start working on your new template!