nce your print book is in production with us for layout, it's time to think about the creation of your full cover--front, back, and spine. You can't just take three pieces to Createspace and hope that they'll get your cover right. Instead, you or your cover designer will go here: Createspace Cover Template Maker.
You or s/he will input your page count and your paper type. Obviously, if you have just started your print layout, you probably won't have a number for your total page count yet. If not, wait for that figure, from your designer, and then input it into the Template maker. You'll get back a PDF template, all in one piece.
As you can see from the image, it's hardly difficult. You will already know your trim size, and you've probably already thought about what paper you want. (Note: if you have images of any kind, it is usually dramatically better to choose WHITE, rather than CREAM. Particularly if you have B&W images! Just a handy tidbit of information for you.)
Your cover designer will then create your final print book cover, marrying the front, back and spine portions of her design. She'll give that back to you in PDF form. When you are ready to publish your book, you'll upload the PDF of the interior and the PDF of the exterior. Createspace then binds the cover to the interior when making your book--and you're off and running.
Note: experienced authors will do many of the Createspace steps in the Dashboard before they have their final PDF or PDFs. We heartily endorse that idea, both for your print book and your eBook. Taking care of the simple, but important, things while you are in production makes sense. Oftentimes, new authors get so excited over a book that they get too rushed to do the Dashboard items (like categories, keywords, the description/blurbs) correctly, or with the care that will help you get your book sold.
Good luck!