You can try vitamin E oil (I buy it from Whole foods) or Mederma.
My daughter hurt herself a couple of months ago and had 3 stitches in the middle of her forehead. The pediatrician recommended Mederma to get rid of the scar as well as avoiding sun exposure and use lots of sun block on it, as sun really will make the scar even worse. I use regular Mederma at home and Mederma with sun block in it (+ regular sun block) outside. I buy it from CVS. My daughter scar has nearly vanished, while my son scar is still as it used to be (he didn't have stitches, a smaller cut and long ago but no cream on it). Now, I'm beginning to use Mederma and vit. E on my son's scar as well.
Good luck!