Hi, you are right that bus is the best way to get there.
The weather is suitable to visit Huangshan during your travel time. However, the temperature differs much in day and night. You'd better take warm jacket in case it is cold on the mountain. You may see the sea of clouds, but may not so thick.
Oh, I think join a tour package would be more safe and convenient. I did so last year. You can according to your budget to choose one package referring to Huangshan Tour Packages(https://www.travelchinaguide.com/package/huangshan.htm) .
Come to Huangshan, you should not miss Yellow Mountain (Huangshan Mountain), Tunxi Ancient Street, Xidi and Hongcun Ancient Villages. For more attractions, you can find in this web.