Create Space Lessons for Book Manufacture
Create Space offers templates to achieve the right cover.
You will find at this page: https://www.createspace.com/Help/Book/Artwork.do
If you need the technical spine specifics, and how to measure, see this page: https://www.createspace.com/Products/Book/CoverPDF.jsp
So on the template page, you can achieve the right size by choosing "custom trim size," and thus make the cover exactly with the right size spine.
You will be sent a png graphic file and a pdf version of the same thing.
You have to have software that uses layers to edit PNG files -- Adobe Photoshop or Adobe Indesign.
The same webpage has a small box explanation of how to use the form at
Incidentally, you can purchase a pre-made design for a book or a kindle ($35) or both ($45) from http://www.coverdesignstudio.com/
How to Have Books Print in True Black
Aaron Shepard explained in early 2015 that you can help your book print out in better clarity by a simple step. He explains:
Update, Mar. 2, 2015—In response to this post, Laura Scott of Toot Sweet Ink reports that she has several CreateSpace black-and-white books on hand, and in every one of them, the type is merely dark gray rather than true black—except in one book, published by me!
I don’t know if that’s due to random print variance, but in case it matters, I should specify how I submit my black-and-white interior files. All text is in grayscale mode, at 100% for pure black. If your app doesn’t output that way, you can fix it in Acrobat Pro with the Convert Colors command—which is what I did for the book she mentions with the RGB output from Word for Mac.
An equivalent is to make it CMYK with 100% black and 0% every other color, which is how InDesign normally outputs black text. Another would be to submit in bitmap mode, with only white or black as possible colors. At least, these should work—but if CreateSpace did an improper conversion, they might not. (link)