Take a crayon. Light colors like white crayons work best with dark easter egg dye colors and dark colors like blue look best with lighter egg colors. Write anything you want (the boys wanted us to write their names) on the dry hard boiled egg BEFORE you dye it.
Then put the egg in the dye.
We were having too much fun but here are our finished eggs with the names blocked off for privacy reasons.
We didn't have a white crayon so we used yellow. It still turned out lovely.
Here in Germany, the dyes for the eggs are much brighter than in the US. I don't know if you can see the difference with my camera, but these eggs were brilliantly colored, (especially the red!)
For more great projects, see Unplug Your Kids.