Format by Amazon Kindle ebook for a Paperback on KDP

I've been having trouble finding the right size and correct margins for distributing my ebook as a paperback, I have the file for the cover of my book, I just need someone to format it for me on KDP. I have a vague sense of how to do it, but I have no experience with it so I don't know if I submit it if it will even be printed correctly.

-Morgan S.