Watch a video demo/tutorial for the NE1 Template Editor.
To edit a template click the "Layout Design" menu button.

The Layout Design page sets the major parameters for the design of your site. It also allows you to import, edit, or delete a template.
To edit a template, click the dropdown box to choose the template to be edited. (Only templates with a name ending in "_e" can currently be edited.) You will then see a page similar to this:

It is important to note that different templates will have different items that are editable. There may be some templates with only a few items that can be edited, while other templates may allow edits that change the look of the entire page.
Watch a video demo/tutorial for the NE1 Template Editor.