The contents of the aether/ folder should not be modified, instead you should create a sub-theme of aether outside of the aether folder by using one of the methods below, the examples assume your theme is in sites/all/themes, but any valid theme directory is ok. The final result should look like this:

sites/all/themes/aether
sites/all/themes/yourthemename

When doing theme creation, template changes, .info changes or code modification, be sure to rebuild the "theme registry". This can be achieved with a drush command "drush cc theme-registry", or by visiting admin/config/performance and clicking clear-cache, or by using the handy devel module.

Drush method

1. Install drush.
2. Navigate to your sites/all/themes/ directory and type: drush aether "Your Theme Name"
3. If you see a new theme with the theme name you typed in sites/all/themes/, then you're done!