How to get rid of scars in week?

okay so i have scars in my arms that have been there for about 4 months but those arent my biggest concern..i wanna go swimming and i have scars in my legs that are fairly medium sized i guess and they arent that dark but they are lighter than my skin.,.btw i have brown skin...so im trying to use mederma because i really really wanna go swimming but is there anything taht can help quicker..it doesnt necessarily have to be medication..and plase dont ask how they got there..thats personal