Hair Color Fades
Okay, so I've been coloring my hair for three and a half years. It started off alright, but for the last year or so, it's been fading far more than it should, and going to a color that is lighter than the dyed color underneath if it is left alone long enough. I want to keep it a medium/dark brown when my original-and what it usually fades to-is a light brown or a dirty blonde. What can I do? Should I dye it twice to work up to the darker? How long should I wait inbetween? What products will help keep that difference?