1) It is totally normal to feel a bit or a lot nervous. I suggest picturing yourself post-procedure with your happy new normal live! This helped me change my anxiety into excitement! Please trust that Dr. Pacik and his staff know what they are doing at every level.
2) I did not bring anything for sitting down, I remember just sitting on one side of my body while commuting back to the hotel. I spent most of the time standing up or laying down anyways.