I died my hair about 2 weeks ago and I want to go natural. Any tips on fading it back to its original color?

My Girlfriend is a hairdresser/makeup artist.. I'm told the best thing to wash your hair with to get dye out is washing up liquid and Tomatoe Ketchup..

I know sounds strange but that's what to do x

Wow that pretty strange! I've got jet black dyed hair! Could you possibly ask your girlfriend what amount of liquid and sauce I've to use to get black out? And how often have you to use it? Daily or just once? What exactly is the routine of doing this? Thanks