The Softproof window displays a PDF that corresponds to what the generated output will look like in your order. If you have previously selected a preview range, the PDF will only contain this range.
The Softproof window requires a PDF viewer such as Adobe PDF in order to display the PDF preview.
Once you are satisfied with the preview, click the Next button and the document will be added to your cart. The Checkout tab will be opened with your current cart contents.