Make sure to put a few kinks in the paper before you begin to glue it down. I suggest gluing the fork down first, then radiating out to the extremities. Don't worry if some of the root does not contact the base. We want some of the root to protrude out of the ground.
Make sure the CA on the root is completely cured before continuing.
Now that the roots are on the bases and the glue is dry, it's time to add the sand.
I use a watered-down white glue to adhere the sand to the base. I like thin white glue better for this application because it wells up next to the root better and creates the illusion that the root is partially underground.
After applying the glue, I dip the base into a container of playground sand laced with various bits that I have collected over the years.
Playground sand is really cheap, and can be purchased at your local DIY store in large 50 lb. bags.
Again, make sure to allow the glue to dry thoroughly (about one hour) before continuing.