Cover File
Cover files for book printing need to be set up in a very specific way. For paperback books that are perfect bound, the book printer is going to need a PDF file that has a back cover, spine and a front cover, from left to right in the proper measurements. If your file is not correct, your book will not look good when it is finished. Do yourself a favor. Hire somebody to make sure that your cover file is prepared and submitted correctly.
By paying to have it done right the first time, you can save a lot of money by not having to go reprint a book because the cove was not correct or lose time and money during the book printing process by having to continually submit new files and get new proofs.
Hard cover book printing will usually require a dust jacket or a printed case wrap. The book printer will need very specific measurements for these files. Ask your book printer for a template that you can give your designer so the file is created properly.