To create a new, empty collection, first open the portfolio and gallery. Select the portfolio and double click to open it. Choose the gallery you want to create a collection in and right click on it. Then select "New Item" from gallery’s context menu.
You will be prompted to enter the collection’s name. Then click <OK> to confirm.
The new collection is created inside the selected gallery and it will be opened. Because there are no images located inside the collection yet, there are no thumbnails to display. You're now ready to start filling your collection.