Ohhh Yeah!! Well, yes and no. Really, I just wanted to bust through the wall ala the Kool Aid Man. Yes, because it will put some kind of coloring on your clothes, and no, because the color doesn't last and not really worth the hassle. I wrote an article last year on the subject of dying clothes with Kool Aid, because this is such a popular question among my readers. Hey, everybody wants a quick fix, and I can't blame you for wanting to dye your clothes with the stuff instead of drinking it. Sorry, I'm just not a fan of the flavor 'purple'.
If you are out to dye a protein fiber like silk or wool, then Kool Aid will certainly work... but it's part of a hot water process that isn't exactly a fun day on the porch with your buds. I think what you're looking for is a cold-water process... you know, squirt the dye onto the clothes all willy-nilly, tra-la-la in the sun.
For this, you should just head on out to the craft store and buy a tie-dye kit. Bite that bullet. These kits are really so cheap and include everything you need, right down to the squirt bottles and rubber bands. They even include instructions for all the different ways to tie up a shirt before you start to dye.
I hate to rain on your Kool Aid parade, but the food colorings in the powder aren't made to stick to a cellulose (plant) material. Plant materials like cotton really need to bond completely with the dye... it's a molecular process that actually changes the structure of the fiber. Kool Aid just can't cut it.