Gallery Assist (GA) installation.

  1. Download GA from Drupal Projects: Gallery Assist.
  2. Move the unpacked Gallery Assist folder (gallery_assist) to the place you have your contributed modules.
  3. Go to Administer > Modules, search in the list for the Gallery Assist entry, check to activate and save the settings.

The folder /sites/default/files/gallery_assist will be created.
At this moment Gallery Assist create for each user with permissions at /sites/default/files/gallery_assist a user folder called with the User-ID.

I recomende after install and  before configure, to create a test gallery, so you have a nosion about default settings.