Mixing: Mix the hair color cream and oxidizer in a 1:1 ratio. 

6% Oxidizer: Used for covering gray hair or for tone-on-tone coloring (not much lightening). 

9% Oxidizer: Used to lighten hair 2-3 levels. 

12% Oxidizer: Used to lighten hair 4-5 levels. 

Application: Apply the mixed dye and oxidizer to your hair, starting from mid-shaft to ends, then roots. 

Processing Time: Leave it on for the recommended time (usually 30-45 minutes). 

Rinsing: Rinse thoroughly with water and apply a conditioner.