A mat or soft rug. Basically, a surface to move your body on comfortably. You could even do it in your bed!
A private place to move, if possible! Does not have to be your own beach, as in the pic. A large closet will suffice! Feel free to use low lights, candles, a soft pillows or blanket, items that make it feel comfortable and cozy.
A speaker, and a way to play an intentionally-curated Spotify playlist, that I send to booked students an hour before class. Downloading Spotify premium is the easiest, and first month is free. Or, you can ask me for the playlist and enter it into iTunes or another music app yourself. The music is an important part of the practice!