I got the idea from pictures on weheartit.com, like this one:
And I think maybe it's childish, but - who cares? It's my room!
Form the stuffing to clouds, needle&thread should help you. Glue rarely works. My experience.
Add 2 strings and stick them to your ceiling with sellotape.
Hope that they won't fall off or deform themselves. I absolutely have no idea :D