Brand as much or as little of your new template as you like e.g. logos or the entire template

1. Go to the Templates tab and select the template you want to edit

2. Select the ‘Field Configuration’ tab
   Here you will find the elements you want to set new values for e.g.logo, colours or fonts.

3. Select the element you want to set values for and tick the ‘Sub-template field’ box 

4. Select 'Save Changes'
5. Next, go to  the ‘Default Branding Values’ tab
Here you will see all the elements that you selected to change on the previous tab
6. Set the new values for these elements
7. On this page you can also hide parts of the template from appearing in the editor
To do this tick the checkbox beside the 'Hide this field in version editor'
8. Select 'Save Changes' 

Useful Links:
What are sub-templates | Configuring sub-templates