Whatever we do gets reflected in our skin. So, if you are not leading a healthy life, it will make your skin loose its firmness. Sun has damaging effects, hence use a sunscreen lotion every time you step out in the sun. Moisturize your skin regularly with a special cream or lotion to keep it well nourished. Regular exercising also allows skin to breathe in more oxygen. And, also keeps your skin elastic. Try not to loose weight too fast. If you start loosing weight at a fast pace, it will result in ugly looking wrinkles. And most importantly, have lots of water. It will help in keeping your skin hydrated and firm.