Unfortunately I don't have a step by step instructable with pictures on this technique to share here with you, but here is how I do this:
1. Take the onion skins, put them in a pot with cold water and boil them for just a few minutes.
2. Take the eggs, check each of them (I don't use the ones that are cracked) and then wash them with dish detergent and warm water, then rinse.
3. Collect leaves of your choice.
4. Take a pair of stockings and cut down one of the legs. This is what you'll be using to tie the eggs in.
5. Take an egg, put a leaf on it (I put it face down, don't really know why...), wrap it tightly in the stocking and tie it with a thread.
6. Repeat with another egg.
7. After you finished tying all your eggs, put them in the pot with the onion skins ( i never take out the skins) and boil them for about 8 minutes to get some hard boiled eggs. Sometimes, when I don't forget, I also add a little vinegar in the pot.
9. After 10 minutes or so take the eggs out of the boiling water and put them in a larger pot with cold water. Cut the stockings to get the eggs out. Let the eggs in cold water long enough so that they cool down.
And that's it!