Follow the link for more specific instructions, but all you do is cut the top off the egg and drain to have a hollow shell as pictured. Place a cotton ball at the bottom of the hollow egg to help with draining. Fill with soil, plant your seed, and grow! I would also find it fun to decorate these eggshells to add a bit more of your creativity to the whole project. Enjoy!
picture borrowed from:www.nebraskapoultry.com