How to tie-dye with food colouring and vinegar
Tie-dying can be a fun project for kids and adults of all ages. True tie-dying needs not only dye but also soda ash. If you're just looking to quickly and easily tie-dye a shirt or two, consider tie-dying with food colouring.
One thing to keep in mind that you should not use cotton clothing -- the food colouring will just wash out. Instead, use a fabric that is wool, silk or nylon.
Pour 1 litre (4 cups) of white vinegar into a medium-size bowl.
Add 1 litre (4 cups) water to the bowl.
Place the cloth or material into the vinegar and water solution. Soak the entire piece in the solution until saturated. Pull the cloth out and squeeze out the excess liquid.
Tie the cloth in rubber bands in any pattern or shape you'd like, to create the tie-dye effect. The bound-off parts will not be dyed.
Place the cloth in a microwave-safe dish or bowl. Drop different colours of food colouring over the entire cloth. Keep in mind that the colours should be placed in the electromagnetic spectrum of light order (red, orange, yellow, green, blue, indigo, violet) to avoid turning the shirt into an orange-brown mess.
Cover the dish with cling film and place the dish in the microwave. Turn the microwave on for one minute. Watch the dish closely; once you see the cling film inflate and condense, remove the dish from the microwave. Allow the cloth to rest for one minute.
Place the dish back into the microwave for five minutes on reduced power (if possible). Continue to watch the cloth closely to ensure is does not steam too much or dry out.
Take the dish out of the microwave and allow the cloth to cool.
Rinse the cloth under cool water until the water runs clear.