How do I prevent sagging skin early in the weight loss process?

I have been exercising regularly for 3 1/2 months at this point. My weight loss progression as been good. I eat 1-2 a day, drink 1 gallon of water a day, ride my stationary bike for 1 hour a day, and do 45 mins worth of floor exercise a day. I workout five days a week not in any specific order as long as a meet the five day workout requirement in a seven day period. I'm losing on average 10 pounds every 3-4 works, BUT now I'm see sagging skin appearing. The most noticeable place is my INNER THIGHS and my STOMACH and a little on my ARMS. WHAT can I do in the early stages of my weight loss process to prevent future sagging skin? I still need to lose at least 100 lbs and I don't want to have skin removal surgery at the end of the process. Please help!!!!

What is your age? Some of it depends on your relative age, also how long you have been big.....etc.