Blue Intensifier

How long should I leave a color enhancer on your hair?

I just got an amplifier color (blue), but I wonder How long should I follow when I use it.

1 High minute!

Sue Devitt Inspiration: Africa

Hoya 55mm Coated Blue Intensifier B+W Tokina Genuine $8.00

Hoya BLUE GREEN RED Didymium Intensifier Filters 72mm $211.05

Hoya BLUE GREEN RED Enhancing Intensifier Filters 49mm $116.55

Hoya BLUE GREEN RED Enhancing Intensifier Filters 55mm $116.55

Hoya BLUE GREEN RED Enhancing Intensifier Filters 58mm $148.05

Hoya BLUE GREEN RED Enhancing Intensifier Filters 62mm $188.55

Hoya BLUE GREEN RED Enhancing Intensifier Filters 67mm $188.55

Hoya BLUE GREEN RED Enhancing Intensifier Filters 72mm $211.05

4 x 2.5z ea.JOICO VERO COLOR INB-Royal Blue Intensifier $19.99

Hoya Blue Intensifier Filter 67mm $40.00