Also, save a copy as a pdf in your phone or computer.
I bought the "bound book" pages from Brownells and put them in a three ring binder.
If you are in MA and you buy a C&R from someone in MA, you must complete both sections of the FA-10 and log all the info in your bound book.
If you buy a C&R from outside of MA, you only complete your portion of the FA-10 and check off "registration". Do not complete the out of state seller's info.
In your bound book, you log the seller's info.
On that note, never ever post which dealers ship to MA, but yes, you can legally have firearms shipped to your door with a C&R.
The reason why you don't want to sign the original is due to the fact that most dealers and suppliers want an actual ink signature copy mailed to them. They accept a photocopy with an ink signature but will not accept a photcopy of a signature. Once you sign your original, you are screwed so don't do it.