Simply die cut a circle from pattern paper that fits the top of your cup. I used the circle die set from Little B. Then, decorate the top of the circle however you want (I used Simon Says Stamp Gnome for the Holidays stamp set on some, and stickers on others), stuff the cup with your goodies, and glue the paper circle over the top of the cup to seal everything in! All done!
I want to enter this project into the Simon Says Stamp Monday Blog Challenge: Holly Jolly Stamping