Take as many eggs as you want to decorate and hard boil them.
1 tsp food colouring (we found blue and green worked great, red and yellow - not so much!)
1 tsp white or wine vinegar
1 tsp salt
1-2 Tbsp hot water (to dissolve the salt)
Put in individual containers big enough to roll the egg in the dye.
Once the eggs are boiled and cooled enough to touch, use a crayon and decorate a pattern on the egg.
Then roll the eggs in your choice of colour and leave to dry on a piece of paper towel or another plate.
Rather than waste it, we used some of our leftover dye with the crayons to make Happy Easter cards.
And the remaining dye will make for an entertaining bath-time the next few nights (oh yes, we do love our coloured baths in this house!)