Seeking legal advice on “returning a firearm” to seller.

I ordered a rifle from an out-of-state FFL. He sent the rifle to my FFL. I filled out the paperwork and my FFL called it in and I picked the rifle up after the waiting period. I do not like the rifle and called the seller (=out-of-state FFL) and he said that I could return it.

Now how do I do it?
Do I send it back?
Or should my FFL send it back?
How is it done legally?
What kind of paperwork do I need to do?
I do not want this gun to be associated with me after I returned it.

I would appreciate the advice of well-informed and experienced people.
Please respond in detail.
Thank you,
Regards,
FRIZ

My understanding is that an FFL can accept a gun from anyone in America. He just has to make notes in his log book.

The seller was an FFL, so couldn't he accept the gun directly.