Okay so my hair is Manic Panic's Hot Hot Pink color and for the longest I've been trying to figure out a way to keep it in longer. I had tried everything: (1) Adding vinager (don't do it, dogs will try to eat you), (2) leaving it to sit over night, and (3) straightening it while the dye was in and nothing worked. It seemed like every other week I was putting dye in. Then one day I remembered what my aunt said may work, mixing hair conditioner and hair dye.
Well it worked! I'll tell you the steps:
1. Get the hair dye of your choice of any brand (works best with Manic Panic).
2. Get a 8 oz. liquid applicator bottle (it works best for roots but you can also use a cup or bowl).
3. Put as much hair dye in it as you need (leave room for to mix the conditioner) and add some conditioner (make sure it's not too much).
5. Make sure it has a creamy look to it.
6. Apply it to selected the area and let it sit for a few hours. It won't damage your hair.
7. Wash it. If you pay attention, you'll notice there's barely any dye coming out. That's because it absorbed it along with the nutrients from the hair conditioner.
8. Final result, it should last a while.