My son and some of his friends did a big production one year. They started when it was really dark. One was lying on a blow-up mattress, pretending to be dead. He raised his arms and started moaning, after the kids had their candy. He was quiet before, so they didn't notice him - he was a few feet off the walkway.
Another was in the bushes by the front porch and had a strobe light, that he turned on when someone had just gotten their candy. They were all wearing black clothes, so they were hard to see. I think there were about 6 of them working together to be scary. They didn't start the scary stuff until after 7:30 - when the littlest kids had come and gone. And if they saw small children coming, they didn't scare them. Word got around fast, and there were big crowds of kids in the street, watching as each group got brave enough to approach the porch. People absolutely loved it, and talked about it for years.
They didn't have "things" that looked scary. It was the dark and them making scary sounds and using lights briefly. Oh, and they had a "scary soundtrack that they played loudly.
If you do this, have unbelievably large amounts of candy. Word gets around -- and everyone wants to come and see the show (and get candy).