On the (reasonable, I think) premise that you're probably not going to Master the skill of Healing yourself, I'm made to understand that Doc Roberts in Shrouded Hills is capable of reducing scarring.
That said, if you do have an interest in removing your scars through your own efforts, you should learn Healing, become proficient enough to seek out Mastery, and once fully Mastered you'll find that scars are easily fixed.
To a lesser extent, those who are not full Masters can successfully reduce scarring. Jayna Stiles, a simple technologist healer from Dernholm, once scored a critical success when healing me after a combat and removed the scar my character had just suffered only one turn ago. I was rather impressed, and quite pleased with the result.

Note: If any of the above non-Roberts means are presently available to you but you don't know how to use them, I recommend buying bandages at the general store, and make sure they remain in the hands of NPC followers who have the Healing skill.

The spell Major Healing should deal with scars as well, though not something to rely on if you have a modest or higher technological aptitude. The various healers in the game should be able to do the job as well, as MackieStingray suggested with Doc Roberts.