Write down any improvements or major repairs that have been done to the home, with dates/costs and leave it for the appraiser to see.
Make note if this home had a lot of showings immediately and had multiple offers.
If you know the reasons why a home in your neighborhood sold for a much lower price that is potentially going to be a comparable for your home then make sure you make them aware of it. (divorce, relocating for a job and needed to move quick, condition of the home was poor, etc.)
Ensure all attic accesses are clear and easily accessible (cars out of the garage if stairs pull down, nothing under the scuttle access in a closet access). Appraisers will not move items to get to the access.
Crawl space accesses should be clear and accessible. They cannot be nailed shut or under a deck.
All appliances that are being left per the purchase agreement are working and plugged in.
All utilities are on for use - appraisers will not turn on any valves.
Ensure the water heater is on.
Ensure any well and/or septic access points are visible. If not, mark them in the yard with either a flag or spray paint.