Rebecca Romijn’s hair color formula 2016
Existing Level: 5 with outgrown highlights
Formula 1: Illumina 10/36 + 30-volume developer
Formula 2: Illumina 10/1 + 40-volume developer
Formula 3: Wella Blondor + 10-volume developer
Formula 4: Illumina 10/1 + 1.9% + Service Color