Dye it green .
To make a yellow shirt purple, you can try using purple fabric dye. Follow the instructions on the dye package to safely dye the shirt. Keep in mind that the color result may vary depending on the original shade of yellow and the dye concentration.
no they are absoluteness not pretty except if you wear them to the beach or you paint then tye dye or something but that is my opinion. Or if you put tyedye peace signs on them!
can you tie dye shirts with food coloring
It's probably because of the food dye in the actual food eg: blue lollypops: they have blue food coloring in them so it'll dye your tongue. Like a stain on a shirt!
berries?
It takes about 24 hours to the tye dye shirt to dry.
Add white to the red.
vinegar
No i believe it is just a colour of shirt
Get a plain white T-shirt and use rubber bands to tie it in places. Dip it it in dye, take it out and squeeze it. Take the rubber bands off and hang it to dry.
I'm assuming you were trying to ask the question, "How do I make yellow dye?", because there's no such thing as yellow food dye in runescape--you can't dye the food in there. Two onions and 5 coins, given to the witch Aggie in Draynor, will produce yellow dye.