The most important thing is to connect with the partner.
Enjoy the sensations and try not to focus too much on whether the hand is in or out. You have to be mentally ready to receive the hand.
For months I had my arse opened by a couple of friends, but I froze as soon as I felt we were almost there. And finally it was another person with smaller hands who entered without me realising. From then on, I knew it was possible and I very quickly started to take any hand that was offered to me.
Get ready to discover a hunger and sensations that are simply phenomenal, and enjoy them and pass them on.
There's nothing more beautiful than a guy with an open arse.