In a previous neighborhood I walked door-to-door inviting people the morning of an impromptu gathering. People looked at me like I had grown two heads and said they didn't think they could come, but everyone cautiously came (bearing too much food I may add) and it became our "Block Party" tradition. You may meet up with some resistance (naysayers abound), but persevere. You may only have a couple people the first few times, but you'll have fun with 4 or 40 people. Don't be too afraid of numbers, people will spill outdoors if it's nice and if the weather is inclement the house will just be full! An FYI: people don't seem to stay as long when it's raining.
For heaven's sake don't make yourself nuts cleaning. NOBODY cares and it will be dark anyway!!! Just open your home, step out of your comfort zone and have fun!