Install a lawn sprinkler that you can turn on remotely.

A friend of mine had a sign on her door that warned about a sleeping baby, please don't make noise and wake the baby!

Turn it on them. Start preaching about religion, politics, or any other divisive topic until they are uncomfortable enough to leave on their own volition.

Wow Ive never had anyone yell at me through the window before. But several times I've been seen at home by soliciting individuals and I've just shut he curtains and not answered the door. If they're payed at all it's by the number of people they sign up, they shouldn't waste much time on someone who clearly doesn't want to buy into what they're selling. If they continue to knock after that you may have to open the door ant tell them youre not interested and to leave your property/stop harassing you. Depending on local laws if you document asking them to leave and they keep at it you can try calling the police on them for harassment. Or you could just call the police right away and claim that they're trying to kick down your door and youre scared for your life. Should get a quick response and will quickly let everyone in the neighborhood know not to knock on your door. Just be careful nkt to cry wolf too much.

I answer the door naked, then relentlessly mock their belief in the make-believe until they fuck off.

average time to fuckoffery: 12 seconds

edit: I've wrecked a Mormon boy's ass or two in my day. they always thanked me.

Counterlogic: Act WAY too interested. Like a crazy person. Unbreakable eye contact. And start asking them very personal questions about themselves with a huge smile on their face.

I usually answer the door holding a hatchet and tell them to get the fuck off my property. Tends to do the trick.

Post "No Trespassing" signs, in many places, those are legally enforceable. If they choose to trespass, call the cops on them.

I don't need a reason to not be bothered at my home, other than being at my home.

I have a side window and just glare at them and shake my head "no" disappointingly. I don't give them the satisfaction of opening the door.

The ring doorbell sounds neat, but I think it's easier to ignore then a human.

I would also follow up with a 1 star review of their company if they behaved that way at my house. And probably shame them on our neighborhood social media pages. With video from my ring doorbell. (I don't have one, but you do.)

Answering the door holding back an aggressive dog helps

Speak to them in some forgein Language, you just need to remember a few phrases to convince them you dont speak their language

I politely say "no thank you" and they move on...

More elaborate sign saying no this... no that... Or try the affirmative, one that states deliveries only, no others, etc.

@snazzy0933
Maybe try putting up signs saying 'ARMED AND DANGEROUS', 'NO TRESPASSING' and 'BEWARE OF DOG'. If you don't have a dog, you can just play dog barking sounds.
A dog on a chain in front of your door is a pretty good deterrent if you're willing to do that though.

If possible put up a gate and a no trespassers sign. Or a beware of dog, they may second guess entering.

If you do have a no trespassing sign and it doesn’t stop, maybe add another sign that says the police will be called and they will be reported for trespassing if they enter the gate without permission.

You could even add that message to your doorbell.

Open the door with your phone recording a video. Nobody is going to be comfortable with that as a conversation starter. When they ask why you're recording, just tell them you're "making a true crime documentary and need footage of the victim."

Try to speak to them in another language