By selecting File -> Create
New Theme from the menu.
New
Theme dialog
In the new theme dialog you:
Use the Theme name field
to specify your themes name. The name can be up to 32 characters long..
Use the Theme content group
to determine what the initial content of you theme will be:
If you want to create a
completely new theme, select Use
default Theme
If you want your new theme
to be based on an existing theme,
select Copy
an existing Theme.
Select Browse… to
open
a file selection dialog. Select the desired theme and click OK.
If you want your new theme
to be based on an example theme,
select Copy
from an example Theme
and select the example theme from the drop down.
Note:
This option will be enabled only when some example themes are added. To add an exmaple theme check Example Themes.