@Clifford10
Clearly you a doing everything right as you have great reviews.
I think it's clear from your details that you live on site - of course some people just don't read. In the automoated (or non-automated) message that you send when a booking is confirmed, put something in along the lines of: Thank you for booking and I look forward to welcoming you into my home.
Follow up messages can end with: I will be here during your stay so can help you with any other questions.
As for the extra guests - we get this sometimes and I put it down to the AirBnB's default which is 1 (ie you don't actually have to make a choice, it does it for you). We always reply to the initial booking with an email saying something like.
Thanks for your booking and to confirm you have booked 1 room for 1 person from xx date.
Please note: if you decide to bring an additional person please let me know so that I can adjust the nightly rate.
Even then you are bound to get someone who is oblivous to all signs, signals and words!
Good luck