Here are my basic supplies. This is an old crock-pot, but they make new ones exactly like this. I can't figure out why they're still making them with the little flower on them though!
The Kool-Aid is the unsweetened version. It should work with the sweetened version too, but you'll need to wash it thoroughly after it's dyed to get rid of the sugar. Not recommended unless you really can't find anything else.
I bought regular food colouring, but apparently Wilton's makes a more professional set in an amazing range of colours. I'll have to try finding some eventually.
Step 1: Set the wool to heat slowly in the crockpot. (It floats, just like cereal.) I needed to push it down several times before it finally wanted to stay under, this is why it looks like there's not quite enough water in the crockpot on this picture.
I added some vinegar to help the dye even though it's not really necessary with Kool-Aid.
This is what it looked like after adding the dye. I'll give you the dyes I placed where according to a clock face: At noon, I added two 7g packets of grape Kool-Aid, at 8 I added two packets of cherry Kool-Aid, and at 3 I added 20 drops of blue food colouring and some more vinegar. Everything was first diluted in a little bit of water.
The photo really shows well what I was seeing with my bare eyes. I was afraid for a moment I was going to end up with mud.
But, lo and behold, this is what my camera saw with the flash!
Better, isn't it? There is a lot of loose dye in the bath, and it seemed to remain that way forever. I'd run to the kitchen every 20 minutes and raise the lid, and poke it, and tell myself to be patient...
The thing with acid dyes is that they need to reach a certain heat, and then, suddenly, everything works the way it should. 20 minutes before I had a bath quite similar to the one above, and then, without warning, I came back to this!
It had suddenly reached the magic temperature and the wool had sucked it all in!
See? No dye left in the bath! All gone! This is how you know it's ready. (The technical term: the dye bath is exhausted.)
Drop the whole mess into a colander to cool by itself (remember, no temperature shock!) and drain. You could let it cool overnight in the dye bath also, but I wanted to do a second batch right away.
I carefully lifted it after a while so the still-hot parts at the bottom had a chance to cool, then I rinsed it in lukewarm water, squeezed it lightly to get some more water out, and hung it in the shower to drip.
Look at the before/after difference! Wow!