All you need to know is in a few paragraphs on Page 20 of the Form 1040-X instructions. 

I did a search for "attach" in those instructions and came up with 43 hits, including a few that were part of the word "attachment(s)."  What I found interesting was that in The Old Days, we would attach copies of both the original form or schedule, and the amended form or schedule, for any that were being changed.  Now, it doesn't look like they want the originals.