For best color results with Ugly Duckling Blue, follow instructions below:
- Pre-lighten Hair to Level 9 or Higher
- Mix 1:1 with developer.
- Use with 20 or 30 Vol developer
- Development time: 30 minutes without heat, 20 minutes with heat.
- For extra color vibrancy, leave to process 10 extra minutes.
- Emulsify and wash with an acidic shampoo.