I had my first fill this morning. I had a bundle of nerves going in, but they were pointless! I never found a step-by step explaniation of the process, so here is mine.
I had to lay down on the table first, so they could make sure they found the port, then they stuck the needle in. I felt the stick (some say the docs use lidocaine, but mine did not) and he 'overfilled' the band. Then I had to sit up and chug (dr's term) room temp Water. Each time I swallowed he asked if I could feel the water and when I could, he would let out some of the fill. This allowed the water to go down. I continued to drink until it felt comfortable. After that, I laid back down, he removed the needle and I went on my merry way.
That was at 9:30. It's now 2:00 and I'm a little hungry, but I also only had a slim-fast since then. It's almost snack time! He did say to stay on liquids for 2 days to make sure the band isn't too tight.
I hope this helps! I think the reason I had nerves was because I didn't know step by step what would happen.