This a project from several years ago that I came across in my keepsake box. We made Valentine's day cards from scratch for my son's elementary school class.
The front of the card featured a clear bubble full of sequins. I started with stiff paper and clear plastic, probably recycled from packaging material. We added sequins between the layers, and then sealed the edges with a tiny bit of hot glue. I think we tried taping two clear layers together, but it was more difficult to go around the curved edges. Then the finished bubble could be taped or glued to the card, and was fun to shake like a snow globe.