Hi Dawana,
Unfortunately, there is nothing you can do about the piece you already completed. If you’re anything like me, you notice more that you don’t like about your pieces than anyone else, so chances are no one else will notice.
To keep this from happening in the future, hold onto the edge of your papers with a fingernail. Ive never had a problem with light brush strokes showing up in a casting. I show my technique for sealing papers with glue in this video:
https://youtu.be/p6DB8uAfecY