I just tell them about Jesus Christ. They don't stay long.
Do you ever wonder how they know a deaf person lives at your address? I had a pair show up at my door, signing, claiming that my neighbor told them I was deaf. I knew that was a lie. I know all my neighbors, and they know that I'm not deaf.
Also, I was interpreting for a deaf consumer at a hospital, and two of them (hearing signers) showed up at the hospital room. They chatted for a while with the deaf consumer, and then left. The deaf consumer was from out of town (and a friend to me), so I was surprised that she had local acquaintances. She told me that she had no clue who they were. So, who violated HPPAA on the hospital staff and let the JW's know that there was deaf person at the hospital, and gave them access to the room (which was in a restricted wing)?
Deaf friends have told me that if they ignore the knocking on the door, the JW's will continue knocking on windows!
In SC, you can answer the door with your shotgun in hand.

(Not really suggesting that.)