Print the picture on paper, cut it out and roll it up, put it in the hole in the top of the ornament and use a toothpick or a chopstick to unroll it inside the bulb.
What Chloe said but if you want the picture to be adhered to the inside of the glass you should use thin paper, which you have cut nicks in around the edge, have applied a loose mixture of Elmers glue to the inside of the bulb and then very carefully push paper into shape probably using the eraser end of a pencil.
Thank you. I want to fix the picture to the glass and do a fake mercury glass finish around it. I think I might paint a small amount first so the
picture is peeking through
Fold it up with out creasing it then it will open inside then fix with a thin object