Use christmas balls or stars, add some christmas lights if you feel like it. Otherwise, you can just display them the way they are. If using bung moss, trim away the root portion with a florist scissor. This will make the bung moss easier to fit to the cone surface and easier to glue. Squeeze glue from the glue gun onto the underside of the moss.
Place clumps together onto foam as close as possible.
Use U-pins if needed. Decorate with miniature balls using U-pins or hot glue. Add Christmas lights if desired. Allow time to set. If the styrofoam cone did not come with the branch pre-built, use a sharp knife to make a snug hole inside the styrofoam cone.