Go to a lot of buffet restaurants and eat all you can to stretch your stomach. However, don't make the mistake I did and fill your plate high when you are starting to feel really full. A couple of years ago I was at King Buffet restaurant and I piled up a plate high with shrimp towards the end of my meal. Big mistake. After a few bites I was stuffed and I still had the entire plate of shrimp to finish. I didn't want to leave a full plate behind so I laboriously finished the plate off shrimp by shrimp. It got so bad towards the end that I actually counted out how many shrimps I had to go to finish them all off and counted down shrimp by shrimp until I finished.
It took me over a year before I could eat a shrimp again. And I still have trouble eating shrimp now.