Please help me correct my "muddy ends"

I colored at home w/Ion Color (6N).  I left it on my roots for 30 minutes and pulled thru to the ends for 10 minutes only.  The front, layered parts of my hair picked up too much of the dye and now the ends are darker than my roots!  I even had a protein filler on my hair.  I'm happy with the color of the roots - how can I remove some of the color from my front layers and ends?  Should I use a clarifying shampoo on those parts only?  TIA!