You might use virgin coconut oil on your skin, as well as increasing your intake of vitamin C.
Vitamin C supports the connective tissue that supports your skin. It will take about three months of supplementation before you see a difference, due to the time it takes for cell renewal.
Coconut oil helps the skin heal. I found that when I started using it, it exfoliated my skin, even though I used to use scrubs, brushes, etc. Gradually, my skin got softer, more even in tone, firmer and scars started fading.
Excercise, of course, is the key. That will build muscles to give your skin shape. Enjoy!