Start by unconditionally loving yourself. Once you can accomplish that, and I mean really do that, not just saying that you do, your flaws become less intrusive on you. You'll also stop focusing on your weaknesses and everyone else's strengths. Even better, you'll find it easier to make the changes that you want, such as getting in shape or losing a bad habit.
Try to stop thinking about it so much. Focus on other things in your life. I think we tend to get obsessed with our bodies, thinking about their flaws, when we could be thinking about other things that are more useful or more fun.
Well start by working out ( get in good shape). Then if you have scars or similar imperfections, there are creams you could use to reduce their appearance. Once you've changed the things that are changeable about your body, you need to start accepting the things that you can't change. Oh and don't compare yourself to other females ( that's a huge confidence killer). Every morning while dressing up, try to see the positive things about your body and embrace them.