Here is my one of my favourite things to do in a hostel (or where ever else I am) for Easter.
My favourite way to colour eggs though, is one I learned from my late grandmother: Onion skins! It's cheap, different, it's eco friendly and so DIY!
How you ask? Pretty easy actually. When being boiled the skins release the pigment, that makes them brown and turn the eggs a really pretty shade of red-ish brown. But here is the step by step guide:
Collect the dry brown onion skins for a while, depending on how many eggs you want to die you may want up to a small shopping bag full of skins. Make sure you store them in a basket or something similar airy that will prevent the skins from growing mold, should there be any moisture left in them. If you're living or working in a hostel it's pretty easy get your hands on that many onion skins. Just ask around, let people know what your are up to, maybe even organise an onion soup competition or make "tarte du flambet" for everyone (yum!).
You will also need some flowers, leaves and maybe grass blades as well as a pair of tights (they can be cheap or even old, since their going to be boiled don't worry too much about germs). Yes, they will survive the boiling water.
Now comes the fiddly part: cut off a piece of your tights and wrap it tightly around the entire egg. Tie the ends together, but remember, be careful the egg is still raw. Where the knot it sitting you will get a pretty cool thai die effect.
Once all your eggs are decorated and covered in tights, place the eggs in a large pot, add the onion skins and cold or lukewarm water and bring the whole thing to boil. Since you probably want hard boiled eggs, let the whole thing boil for about 8 minutes. Stir the whole thing every now and then, so all sides of your eggs get a bit of colour. Be careful not to get any of the onion water on your clothes since it might leave stains you won't get rid of.
If you want to make them nice and shiny you can rub some oil or butter on them.