A while back I did 2 tutorials on how to bleach and dye hair on my tumblr. I'm going to repost them here, but you can click below for the originals.
Click here for Part 1
Click here for Part 2
Click here for hair dye FAQ
How to Dye Hair Bright Colors
Part 1: Bleach
Vol 40 developer, Bleach Powder, Mixing Bowl, Gloves
I’ll only be doing my roots for this tutorial since the rest of my hair is already light enough from being bleached white previously.
Mix vol 40 developer with bleach powder. This combination will be very powerful and quick compared to supermarket box bleaches so be careful and watch how it develops. I don’t need to leave mine in any more than… 30 minutes or so from when I start applying it.
I start with the most visible areas: my center part, bangs, and nape of the neck (I wear my hair in a high pony often). I try not to get bleach on parts of my hair that have already been bleached, but my bangs grow out too quickly for them to get damaged. A hairdryer once the bleach is all applied will speed up the development.
Try to go as light as you can since that will lead to brighter colors once you dye it. To get rid of a brassy or yellow town if you rinse the bleach out too early, try a toner or a bit of purple shampoo in conditioner.
Wash the bleach out of your hair without using conditioner and let it dry. You are now ready to add dye!
How to Dye Hair Bright Colors
Part 2: Color
Dye (Ion, Special Effects, Manic Panic), Conditioner (Aussie Moist), Gloves
I start by mixing up my dyes with Conditioner. I use Aussie Moist. For typical, bright colors, I will use a 50/50 mixture. This will not dilute the dye too much, but really stretches the life of your dye and helps it soak into your hair. To lighten the color a little bit but not quite a pastel, I would use a 1/3 ratio. For pastels, I would greatly dilute the dye, maybe 1/5. The only color I do not personally dilute is Yellow.
The colors I am using in this round of dye:
Light Blue (Ion Aqua and Special Effect’s Blue Haired Freak + varying amounts of conditioner)
Blue (SE Blue haired Freak and Manic Panic purple haze + conditioner)
Green (mix of Ion Teal and MP’s Electric Banana + conditioner)
Yellow (MP’s Electric Banana)
I typically apply my colors in order from light to dark and in a similar order to where I applied the bleach. For ombre type bangs, I will usually apply the darker color, maybe without being diluted, and then dilute it with more and more conditioner as I approach my roots. Once everything is dyed, I will use a hairdryer to speed up the absorption. There’s no real set time I wash the dye out. Normally I will test to see if my hair has absorbed all the color by rubbing a chunk of my hair. If white or pastel conditioner comes off on my hand, I’ll know my hair’s ready to wash out.
This method lasts me about 4 weeks of bright bright hair, 3 weeks of somewhat lighter colors, and pastel hair for over a month after that! I usually end up redoing my roots every 5 weeks so my hair rarely gets to the pastel stage. Hope this answered some questions!