How do I get rid of scars?

I've got a pretty big scar on my left arm. I don't remember what it was from, but I've had it as long as I can remember. It is slightly raised, but my main problem with the scar is it is darker than the rest of my skin, almost a purple ish color.How do I get rid of scars?
Go to your local drug store they sell several scar lighteners as well as cover-ups also you could try Palmers Coco Butter they sell it just about everywhere it's a lotion. It helps with scars and stretchmarks. I've used it before it might take some time but it works.How do I get rid of scars?
impossible