You can go to the gunslinger/healer(Doc) in the Shrouded Hills. Also, a critical success in the Healing skill will heal scars. Use a fate point if you have to. You may have to be an expert in healing, though I am not sure. The other way is a Major Healing spell.
Buy bandages and give them to Virgil or Jayna. When you are injured they automatically heal you. While they are doing that, they fix your scars.